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| gitHub |
| <svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></a></nav> <ul class="sidebar-links"><li><section class="sidebar-group depth-0"><p class="sidebar-heading"><span>IoTDB User Guide (V0.9.x)</span> <!----></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>0-Get Started</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>1-Overview</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>2-Concept</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>3-Server</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading open"><span>4-Client</span> <span class="arrow down"></span></p> <ul class="sidebar-links sidebar-group-items"><li><a href="/UserGuide/V0.9.x/4-Client/1-Command Line Interface.html" class="sidebar-link">Command Line Interface</a></li><li><a href="/UserGuide/V0.9.x/4-Client/2-Programming - JDBC.html" class="sidebar-link">JDBC</a></li><li><a href="/UserGuide/V0.9.x/4-Client/3-Programming - Session.html" class="sidebar-link">Session</a></li><li><a href="/UserGuide/V0.9.x/4-Client/4-Programming - Other Languages.html" class="sidebar-link">Other Languages</a></li><li><a href="/UserGuide/V0.9.x/4-Client/5-Programming - TsFile API.html" class="active sidebar-link">TsFile API</a></li></ul></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>5-Operation Manual</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>6-System Tools</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>7-Ecosystem Integration</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>8-System Design</span> <span class="arrow right"></span></p> <!----></section></li></ul> </aside> <main class="page"> <div class="content content__default"><h1 id="programming-tsfile-api"><a href="#programming-tsfile-api" class="header-anchor">#</a> Programming - TsFile API</h1> <p>TsFile is a file format of Time Series we used in IoTDB. In this section, we would like to introduce the usage of this file format.</p> <h2 id="tsfile-libaray-installation"><a href="#tsfile-libaray-installation" class="header-anchor">#</a> TsFile libaray Installation</h2> <p>There are two ways to use TsFile in your own project.</p> <ul><li><p>Using as jars:</p> <ul><li><p>Compile the source codes and build to jars</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>git clone https://github.com/apache/incubator-iotdb.git |
| cd tsfile/ |
| mvn clean package -Dmaven.test.skip=true |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br></div></div><p>Then, all the jars can be get in folder named <code>target/</code>. Import <code>target/tsfile-0.9.2-jar-with-dependencies.jar</code> to your project.</p></li></ul></li> <li><p>Using as a maven dependency:</p> <p>Compile source codes and deploy to your local repository in three steps:</p> <ul><li><p>Get the source codes</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>git clone https://github.com/apache/incubator-iotdb.git |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div></li> <li><p>Compile the source codes and deploy</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>cd tsfile/ |
| mvn clean install -Dmaven.test.skip=true |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div></li> <li><p>add dependencies into your project:</p> <div class="language- line-numbers-mode"><pre class="language-text"><code> <dependency> |
| <groupId>org.apache.iotdb</groupId> |
| <artifactId>tsfile</artifactId> |
| <version>0.9.2</version> |
| </dependency> |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br></div></div></li></ul> <p>Or, you can download the dependencies from official Maven repository:</p> <ul><li><p>First, find your maven <code>settings.xml</code> on path: <code>${username}\.m2\settings.xml</code> |
| , add this <code><profile></code> to <code><profiles></code>:</p> <div class="language- line-numbers-mode"><pre class="language-text"><code> <profile> |
| <id>allow-snapshots</id> |
| <activation><activeByDefault>true</activeByDefault></activation> |
| <repositories> |
| <repository> |
| <id>apache.snapshots</id> |
| <name>Apache Development Snapshot Repository</name> |
| <url>https://repository.apache.org/content/repositories/snapshots/</url> |
| <releases> |
| <enabled>false</enabled> |
| </releases> |
| <snapshots> |
| <enabled>true</enabled> |
| </snapshots> |
| </repository> |
| </repositories> |
| </profile> |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br></div></div></li> <li><p>Then add dependencies into your project:</p> <div class="language- line-numbers-mode"><pre class="language-text"><code> <dependency> |
| <groupId>org.apache.iotdb</groupId> |
| <artifactId>tsfile</artifactId> |
| <version>0.9.2</version> |
| </dependency> |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br></div></div></li></ul></li></ul> <h2 id="tsfile-usage"><a href="#tsfile-usage" class="header-anchor">#</a> TSFile Usage</h2> <p>This section demonstrates the detailed usages of TsFile.</p> <h3 id="time-series-data"><a href="#time-series-data" class="header-anchor">#</a> Time-series Data</h3> <p>A time-series is considered as a sequence of quadruples. A quadruple is defined as (device, measurement, time, value).</p> <ul><li><p><strong>measurement</strong>: A physical or formal measurement that a time-series is taking, e.g., the temperature of a city, the |
| sales number of some goods or the speed of a train at different times. As a traditional sensor (like a thermometer) also |
| takes a single measurement and produce a time-series, we will use measurement and sensor interchangeably below.</p></li> <li><p><strong>device</strong>: A device refers to an entity that is taking several measurements (producing multiple time-series), e.g., |
| a running train monitors its speed, oil meter, miles it has run, current passengers each is conveyed to a time-series.</p></li></ul> <p>Table 1 illustrates a set of time-series data. The set showed in the following table contains one device named "device_1" |
| with three measurements named "sensor_1", "sensor_2" and "sensor_3".</p> <table style="text-align:center;"><tr><th colspan="6">device_1</th></tr> <tr><th colspan="2">sensor_1</th><th colspan="2">sensor_2</th><th colspan="2">sensor_3</th></tr> <tr><th>time</th><th>value</th><th>time</th><th>value</th><th>time</th><th>value</th></tr> <tr><td>1</td><td>1.2</td><td>1</td><td>20</td><td>2</td><td>50</td></tr> <tr><td>3</td><td>1.4</td><td>2</td><td>20</td><td>4</td><td>51</td></tr> <tr><td>5</td><td>1.1</td><td>3</td><td>21</td><td>6</td><td>52</td></tr> <tr><td>7</td><td>1.8</td><td>4</td><td>20</td><td>8</td><td>53</td></tr></table> <span>A set of time-series data</span> <p><strong>One Line of Data</strong>: In many industrial applications, a device normally contains more than one sensor and these sensors |
| may have values at a same timestamp, which is called one line of data.</p> <p>Formally, one line of data consists of a <code>device_id</code>, a timestamp which indicates the milliseconds since January 1, |
| 1970, 00:00:00, and several data pairs composed of <code>measurement_id</code> and corresponding <code>value</code>. All data pairs in one |
| line belong to this <code>device_id</code> and have the same timestamp. If one of the <code>measurements</code> does not have a <code>value</code> |
| in the <code>timestamp</code>, use a space instead(Actually, TsFile does not store null values). Its format is shown as follow:</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>device_id, timestamp, <measurement_id, value>... |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p>An example is illustrated as follow. In this example, the data type of two measurements are <code>INT32</code>, <code>FLOAT</code> respectively.</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>device_1, 1490860659000, m1, 10, m2, 12.12 |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><h3 id="writing-tsfile"><a href="#writing-tsfile" class="header-anchor">#</a> Writing TsFile</h3> <h4 id="generate-a-tsfile-file"><a href="#generate-a-tsfile-file" class="header-anchor">#</a> Generate a TsFile File.</h4> <p>A TsFile can be generated by following three steps and the complete code will be given in the section "Example for writing TsFile".</p> <ul><li><p>First, construct a <code>TsFileWriter</code> instance.</p> <p>Here are the available constructors:</p> <ul><li>Without pre-defined schema</li></ul> <div class="language- line-numbers-mode"><pre class="language-text"><code>public TsFileWriter(File file) throws IOException |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><ul><li>With pre-defined schema</li></ul> <div class="language- line-numbers-mode"><pre class="language-text"><code>public TsFileWriter(File file, Schema schema) throws IOException |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p>This one is for using the HDFS file system. <code>TsFileOutput</code> can be an instance of class <code>HDFSOutput</code>.</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>public TsFileWriter(TsFileOutput output, Schema schema) throws IOException |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p>If you want to set some TSFile configuration on your own, you could use param <code>config</code>. For example:</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>TSFileConfig conf = new TSFileConfig(); |
| conf.setTSFileStorageFs("HDFS"); |
| TsFileWriter tsFileWriter = new TsFileWriter(file, schema, conf); |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br></div></div><p>In this example, data files will be stored in HDFS, instead of local file system. If you'd like to store data files in local file system, you can use <code>conf.setTSFileStorageFs("LOCAL")</code>, which is also the default config.</p> <p>You can also config the ip and port of your HDFS by <code>config.setHdfsIp(...)</code> and <code>config.setHdfsPort(...)</code>. The default ip is <code>localhost</code> and default port is <code>9000</code>.</p> <p><strong>Parameters:</strong></p> <ul><li><p>file : The TsFile to write</p></li> <li><p>schema : The file schemas, will be introduced in next part.</p></li> <li><p>config : The config of TsFile.</p></li></ul></li> <li><p>Second, add measurements</p> <p>Or you can make an instance of class <code>Schema</code> first and pass this to the constructor of class <code>TsFileWriter</code></p> <p>The class <code>Schema</code> contains a map whose key is the name of one measurement schema, and the value is the schema itself.</p> <p>Here are the interfaces:</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>// Create an empty Schema or from an existing map |
| public Schema() |
| public Schema(Map<String, MeasurementSchema> measurements) |
| // Use this two interfaces to add measurements |
| public void registerMeasurement(MeasurementSchema descriptor) |
| public void registerMeasurements(Map<String, MeasurementSchema> measurements) |
| // Some useful getter and checker |
| public TSDataType getMeasurementDataType(String measurementId) |
| public MeasurementSchema getMeasurementSchema(String measurementId) |
| public Map<String, MeasurementSchema> getAllMeasurementSchema() |
| public boolean hasMeasurement(String measurementId) |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br></div></div><p>You can always use the following interface in <code>TsFileWriter</code> class to add additional measurements: |
| </p> <div class="language- line-numbers-mode"><pre class="language-text"><code>public void addMeasurement(MeasurementSchema measurementSchema) throws WriteProcessException |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p>The class <code>MeasurementSchema</code> contains the information of one measurement, there are several constructors:</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>public MeasurementSchema(String measurementId, TSDataType type, TSEncoding encoding) |
| public MeasurementSchema(String measurementId, TSDataType type, TSEncoding encoding, CompressionType compressionType) |
| public MeasurementSchema(String measurementId, TSDataType type, TSEncoding encoding, CompressionType compressionType, |
| Map<String, String> props) |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br></div></div><p><strong>Parameters:</strong> |
| </p> <ul><li><p>measurementID: The name of this measurement, typically the name of the sensor.</p></li> <li><p>type: The data type, now support six types: <code>BOOLEAN</code>, <code>INT32</code>, <code>INT64</code>, <code>FLOAT</code>, <code>DOUBLE</code>, <code>TEXT</code>;</p></li> <li><p>encoding: The data encoding. See <a href="/UserGuide/V0.9.x/2-Concept/3-Encoding.html">Chapter 2-3</a>.</p></li> <li><p>compression: The data compression. Now supports <code>UNCOMPRESSED</code> and <code>SNAPPY</code>.</p></li> <li><p>props: Properties for special data types.Such as <code>max_point_number</code> for <code>FLOAT</code> and <code>DOUBLE</code>, <code>max_string_length</code> for |
| <code>TEXT</code>. Use as string pairs into a map such as ("max_point_number", "3").</p></li></ul> <blockquote><p><strong>Notice:</strong> Although one measurement name can be used in multiple deltaObjects, the properties cannot be changed. I.e. |
| it's not allowed to add one measurement name for multiple times with different type or encoding. |
| Here is a bad example:</p></blockquote> <div class="language- extra-class"><pre><code> // The measurement "sensor_1" is float type |
| addMeasurement(new MeasurementSchema("sensor_1", TSDataType.FLOAT, TSEncoding.RLE)); |
| |
| // This call will throw a WriteProcessException exception |
| addMeasurement(new MeasurementSchema("sensor_1", TSDataType.INT32, TSEncoding.RLE)); |
| </code></pre></div></li> <li><p>Third, insert and write data continually.</p> <p>Use this interface to create a new <code>TSRecord</code>(a timestamp and device pair).</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>public TSRecord(long timestamp, String deviceId) |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p>Then create a <code>DataPoint</code>(a measurement and value pair), and use the addTuple method to add the DataPoint to the correct |
| TsRecord.</p> <p>Use this method to write</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>public void write(TSRecord record) throws IOException, WriteProcessException |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div></li> <li><p>Finally, call <code>close</code> to finish this writing process.</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>public void close() throws IOException |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div></li></ul> <h4 id="example-for-writing-a-tsfile"><a href="#example-for-writing-a-tsfile" class="header-anchor">#</a> Example for writing a TsFile</h4> <p>You should install TsFile to your local maven repository.</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>mvn clean install -pl tsfile -am -DskipTests |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p>You could write a TsFile by constructing <strong>TSRecord</strong> if you have the <strong>non-aligned</strong> (e.g. not all sensors contain values) time series data.</p> <p>A more thorough example can be found at <code>/example/tsfile/src/main/java/org/apache/iotdb/tsfile/TsFileWriteWithTSRecord.java</code></p> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile</span><span class="token punctuation">;</span> |
| |
| <span class="token keyword">import</span> <span class="token namespace">java<span class="token punctuation">.</span>io</span><span class="token punctuation">.</span><span class="token class-name">File</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>file<span class="token punctuation">.</span>metadata<span class="token punctuation">.</span>enums</span><span class="token punctuation">.</span><span class="token class-name">TSDataType</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>file<span class="token punctuation">.</span>metadata<span class="token punctuation">.</span>enums</span><span class="token punctuation">.</span><span class="token class-name">TSEncoding</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>write</span><span class="token punctuation">.</span><span class="token class-name">TsFileWriter</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>write<span class="token punctuation">.</span>record</span><span class="token punctuation">.</span><span class="token class-name">TSRecord</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>write<span class="token punctuation">.</span>record<span class="token punctuation">.</span>datapoint</span><span class="token punctuation">.</span><span class="token class-name">DataPoint</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>write<span class="token punctuation">.</span>record<span class="token punctuation">.</span>datapoint</span><span class="token punctuation">.</span><span class="token class-name">FloatDataPoint</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>write<span class="token punctuation">.</span>record<span class="token punctuation">.</span>datapoint</span><span class="token punctuation">.</span><span class="token class-name">IntDataPoint</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>write<span class="token punctuation">.</span>schema</span><span class="token punctuation">.</span><span class="token class-name">MeasurementSchema</span><span class="token punctuation">;</span> |
| <span class="token comment">/** |
| * An example of writing data to TsFile |
| * It uses the interface: |
| * public void addMeasurement(MeasurementSchema MeasurementSchema) throws WriteProcessException |
| */</span> |
| <span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">TsFileWriteWithTSRecord</span> <span class="token punctuation">{</span> |
| |
| <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span> args<span class="token punctuation">[</span><span class="token punctuation">]</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> |
| <span class="token keyword">try</span> <span class="token punctuation">{</span> |
| <span class="token class-name">String</span> path <span class="token operator">=</span> <span class="token string">"test.tsfile"</span><span class="token punctuation">;</span> |
| <span class="token class-name">File</span> f <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">File</span><span class="token punctuation">(</span>path<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token keyword">if</span> <span class="token punctuation">(</span>f<span class="token punctuation">.</span><span class="token function">exists</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> |
| f<span class="token punctuation">.</span><span class="token function">delete</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> |
| <span class="token class-name">TsFileWriter</span> tsFileWriter <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">TsFileWriter</span><span class="token punctuation">(</span>f<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| |
| <span class="token comment">// add measurements into file schema</span> |
| tsFileWriter |
| <span class="token punctuation">.</span><span class="token function">addMeasurement</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">MeasurementSchema</span><span class="token punctuation">(</span><span class="token string">"sensor_1"</span><span class="token punctuation">,</span> <span class="token class-name">TSDataType</span><span class="token punctuation">.</span>INT64<span class="token punctuation">,</span> <span class="token class-name">TSEncoding</span><span class="token punctuation">.</span>RLE<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| tsFileWriter |
| <span class="token punctuation">.</span><span class="token function">addMeasurement</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">MeasurementSchema</span><span class="token punctuation">(</span><span class="token string">"sensor_2"</span><span class="token punctuation">,</span> <span class="token class-name">TSDataType</span><span class="token punctuation">.</span>INT64<span class="token punctuation">,</span> <span class="token class-name">TSEncoding</span><span class="token punctuation">.</span>RLE<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| tsFileWriter |
| <span class="token punctuation">.</span><span class="token function">addMeasurement</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">MeasurementSchema</span><span class="token punctuation">(</span><span class="token string">"sensor_3"</span><span class="token punctuation">,</span> <span class="token class-name">TSDataType</span><span class="token punctuation">.</span>INT64<span class="token punctuation">,</span> <span class="token class-name">TSEncoding</span><span class="token punctuation">.</span>RLE<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| |
| <span class="token comment">// construct TSRecord</span> |
| <span class="token class-name">TSRecord</span> tsRecord <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">TSRecord</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">,</span> <span class="token string">"device_1"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token class-name">DataPoint</span> dPoint1 <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">LongDataPoint</span><span class="token punctuation">(</span><span class="token string">"sensor_1"</span><span class="token punctuation">,</span> <span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token class-name">DataPoint</span> dPoint2 <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">LongDataPoint</span><span class="token punctuation">(</span><span class="token string">"sensor_2"</span><span class="token punctuation">,</span> <span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token class-name">DataPoint</span> dPoint3 <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">LongDataPoint</span><span class="token punctuation">(</span><span class="token string">"sensor_3"</span><span class="token punctuation">,</span> <span class="token number">3</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| tsRecord<span class="token punctuation">.</span><span class="token function">addTuple</span><span class="token punctuation">(</span>dPoint1<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| tsRecord<span class="token punctuation">.</span><span class="token function">addTuple</span><span class="token punctuation">(</span>dPoint2<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| tsRecord<span class="token punctuation">.</span><span class="token function">addTuple</span><span class="token punctuation">(</span>dPoint3<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| |
| <span class="token comment">// write TSRecord</span> |
| tsFileWriter<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>tsRecord<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| |
| <span class="token comment">// close TsFile</span> |
| tsFileWriter<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> <span class="token keyword">catch</span> <span class="token punctuation">(</span><span class="token class-name">Throwable</span> e<span class="token punctuation">)</span> <span class="token punctuation">{</span> |
| e<span class="token punctuation">.</span><span class="token function">printStackTrace</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">println</span><span class="token punctuation">(</span>e<span class="token punctuation">.</span><span class="token function">getMessage</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> |
| <span class="token punctuation">}</span> |
| <span class="token punctuation">}</span> |
| |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br><span class="line-number">36</span><br><span class="line-number">37</span><br><span class="line-number">38</span><br><span class="line-number">39</span><br><span class="line-number">40</span><br><span class="line-number">41</span><br><span class="line-number">42</span><br><span class="line-number">43</span><br><span class="line-number">44</span><br><span class="line-number">45</span><br><span class="line-number">46</span><br><span class="line-number">47</span><br><span class="line-number">48</span><br><span class="line-number">49</span><br><span class="line-number">50</span><br><span class="line-number">51</span><br><span class="line-number">52</span><br><span class="line-number">53</span><br><span class="line-number">54</span><br><span class="line-number">55</span><br><span class="line-number">56</span><br></div></div><p>You could write a TsFile by constructing <strong>RowBatch</strong> if you have the <strong>aligned</strong> time series data.</p> <p>A more thorough example can be found at <code>/example/tsfile/src/main/java/org/apache/iotdb/tsfile/TsFileWriteWithRowBatch.java</code></p> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile</span><span class="token punctuation">;</span> |
| |
| <span class="token keyword">import</span> <span class="token namespace">java<span class="token punctuation">.</span>io</span><span class="token punctuation">.</span><span class="token class-name">File</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>file<span class="token punctuation">.</span>metadata<span class="token punctuation">.</span>enums</span><span class="token punctuation">.</span><span class="token class-name">TSDataType</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>file<span class="token punctuation">.</span>metadata<span class="token punctuation">.</span>enums</span><span class="token punctuation">.</span><span class="token class-name">TSEncoding</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>write</span><span class="token punctuation">.</span><span class="token class-name">TsFileWriter</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>write<span class="token punctuation">.</span>schema</span><span class="token punctuation">.</span><span class="token class-name">Schema</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>write<span class="token punctuation">.</span>schema</span><span class="token punctuation">.</span><span class="token class-name">MeasurementSchema</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>write<span class="token punctuation">.</span>record</span><span class="token punctuation">.</span><span class="token class-name">RowBatch</span><span class="token punctuation">;</span> |
| <span class="token comment">/** |
| * An example of writing data with RowBatch to TsFile |
| */</span> |
| <span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">TsFileWriteWithRowBatch</span> <span class="token punctuation">{</span> |
| |
| <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token punctuation">{</span> |
| <span class="token keyword">try</span> <span class="token punctuation">{</span> |
| <span class="token class-name">String</span> path <span class="token operator">=</span> <span class="token string">"test.tsfile"</span><span class="token punctuation">;</span> |
| <span class="token class-name">File</span> f <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">File</span><span class="token punctuation">(</span>path<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token keyword">if</span> <span class="token punctuation">(</span>f<span class="token punctuation">.</span><span class="token function">exists</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> |
| f<span class="token punctuation">.</span><span class="token function">delete</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> |
| |
| <span class="token class-name">Schema</span> schema <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">Schema</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| |
| <span class="token comment">// the number of rows to include in the row batch</span> |
| <span class="token keyword">int</span> rowNum <span class="token operator">=</span> <span class="token number">1000000</span><span class="token punctuation">;</span> |
| <span class="token comment">// the number of values to include in the row batch</span> |
| <span class="token keyword">int</span> sensorNum <span class="token operator">=</span> <span class="token number">10</span><span class="token punctuation">;</span> |
| |
| <span class="token comment">// add measurements into file schema (all with INT64 data type)</span> |
| <span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">int</span> i <span class="token operator">=</span> <span class="token number">0</span><span class="token punctuation">;</span> i <span class="token operator"><</span> sensorNum<span class="token punctuation">;</span> i<span class="token operator">++</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> |
| schema<span class="token punctuation">.</span><span class="token function">registerMeasurement</span><span class="token punctuation">(</span> |
| <span class="token keyword">new</span> <span class="token class-name">MeasurementSchema</span><span class="token punctuation">(</span><span class="token string">"sensor_"</span> <span class="token operator">+</span> <span class="token punctuation">(</span>i <span class="token operator">+</span> <span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token class-name">TSDataType</span><span class="token punctuation">.</span>INT64<span class="token punctuation">,</span> <span class="token class-name">TSEncoding</span><span class="token punctuation">.</span>TS_2DIFF<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> |
| |
| <span class="token comment">// add measurements into TSFileWriter</span> |
| <span class="token class-name">TsFileWriter</span> tsFileWriter <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">TsFileWriter</span><span class="token punctuation">(</span>f<span class="token punctuation">,</span> schema<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| |
| <span class="token comment">// construct the row batch</span> |
| <span class="token class-name">RowBatch</span> rowBatch <span class="token operator">=</span> schema<span class="token punctuation">.</span><span class="token function">createRowBatch</span><span class="token punctuation">(</span><span class="token string">"device_1"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| |
| <span class="token keyword">long</span><span class="token punctuation">[</span><span class="token punctuation">]</span> timestamps <span class="token operator">=</span> rowBatch<span class="token punctuation">.</span>timestamps<span class="token punctuation">;</span> |
| <span class="token class-name">Object</span><span class="token punctuation">[</span><span class="token punctuation">]</span> values <span class="token operator">=</span> rowBatch<span class="token punctuation">.</span>values<span class="token punctuation">;</span> |
| |
| <span class="token keyword">long</span> timestamp <span class="token operator">=</span> <span class="token number">1</span><span class="token punctuation">;</span> |
| <span class="token keyword">long</span> value <span class="token operator">=</span> <span class="token number">1000000L</span><span class="token punctuation">;</span> |
| |
| <span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">int</span> r <span class="token operator">=</span> <span class="token number">0</span><span class="token punctuation">;</span> r <span class="token operator"><</span> rowNum<span class="token punctuation">;</span> r<span class="token operator">++</span><span class="token punctuation">,</span> value<span class="token operator">++</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> |
| <span class="token keyword">int</span> row <span class="token operator">=</span> rowBatch<span class="token punctuation">.</span>batchSize<span class="token operator">++</span><span class="token punctuation">;</span> |
| timestamps<span class="token punctuation">[</span>row<span class="token punctuation">]</span> <span class="token operator">=</span> timestamp<span class="token operator">++</span><span class="token punctuation">;</span> |
| <span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">int</span> i <span class="token operator">=</span> <span class="token number">0</span><span class="token punctuation">;</span> i <span class="token operator"><</span> sensorNum<span class="token punctuation">;</span> i<span class="token operator">++</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> |
| <span class="token keyword">long</span><span class="token punctuation">[</span><span class="token punctuation">]</span> sensor <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token keyword">long</span><span class="token punctuation">[</span><span class="token punctuation">]</span><span class="token punctuation">)</span> values<span class="token punctuation">[</span>i<span class="token punctuation">]</span><span class="token punctuation">;</span> |
| sensor<span class="token punctuation">[</span>row<span class="token punctuation">]</span> <span class="token operator">=</span> value<span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> |
| <span class="token comment">// write RowBatch to TsFile</span> |
| <span class="token keyword">if</span> <span class="token punctuation">(</span>rowBatch<span class="token punctuation">.</span>batchSize <span class="token operator">==</span> rowBatch<span class="token punctuation">.</span><span class="token function">getMaxBatchSize</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> |
| tsFileWriter<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>rowBatch<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| rowBatch<span class="token punctuation">.</span><span class="token function">reset</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> |
| <span class="token punctuation">}</span> |
| <span class="token comment">// write RowBatch to TsFile</span> |
| <span class="token keyword">if</span> <span class="token punctuation">(</span>rowBatch<span class="token punctuation">.</span>batchSize <span class="token operator">!=</span> <span class="token number">0</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> |
| tsFileWriter<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>rowBatch<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| rowBatch<span class="token punctuation">.</span><span class="token function">reset</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> |
| |
| <span class="token comment">// close TsFile</span> |
| tsFileWriter<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> <span class="token keyword">catch</span> <span class="token punctuation">(</span><span class="token class-name">Throwable</span> e<span class="token punctuation">)</span> <span class="token punctuation">{</span> |
| e<span class="token punctuation">.</span><span class="token function">printStackTrace</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">println</span><span class="token punctuation">(</span>e<span class="token punctuation">.</span><span class="token function">getMessage</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> |
| <span class="token punctuation">}</span> |
| <span class="token punctuation">}</span> |
| |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br><span class="line-number">36</span><br><span class="line-number">37</span><br><span class="line-number">38</span><br><span class="line-number">39</span><br><span class="line-number">40</span><br><span class="line-number">41</span><br><span class="line-number">42</span><br><span class="line-number">43</span><br><span class="line-number">44</span><br><span class="line-number">45</span><br><span class="line-number">46</span><br><span class="line-number">47</span><br><span class="line-number">48</span><br><span class="line-number">49</span><br><span class="line-number">50</span><br><span class="line-number">51</span><br><span class="line-number">52</span><br><span class="line-number">53</span><br><span class="line-number">54</span><br><span class="line-number">55</span><br><span class="line-number">56</span><br><span class="line-number">57</span><br><span class="line-number">58</span><br><span class="line-number">59</span><br><span class="line-number">60</span><br><span class="line-number">61</span><br><span class="line-number">62</span><br><span class="line-number">63</span><br><span class="line-number">64</span><br><span class="line-number">65</span><br><span class="line-number">66</span><br><span class="line-number">67</span><br><span class="line-number">68</span><br><span class="line-number">69</span><br><span class="line-number">70</span><br><span class="line-number">71</span><br><span class="line-number">72</span><br><span class="line-number">73</span><br><span class="line-number">74</span><br><span class="line-number">75</span><br></div></div><h3 id="interface-for-reading-tsfile"><a href="#interface-for-reading-tsfile" class="header-anchor">#</a> Interface for Reading TsFile</h3> <h4 id="before-the-start"><a href="#before-the-start" class="header-anchor">#</a> Before the Start</h4> <p>The set of time-series data in section "Time-series Data" is used here for a concrete introduction in this section. The set showed in the following table contains one deltaObject named "device_1" with three measurements named "sensor_1", "sensor_2" and "sensor_3". And the measurements has been simplified to do a simple illustration, which contains only 4 time-value pairs each.</p> <table style="text-align:center;"><tr><th colspan="6">device_1</th></tr> <tr><th colspan="2">sensor_1</th><th colspan="2">sensor_2</th><th colspan="2">sensor_3</th></tr> <tr><th>time</th><th>value</th><th>time</th><th>value</th><th>time</th><th>value</th></tr> <tr><td>1</td><td>1.2</td><td>1</td><td>20</td><td>2</td><td>50</td></tr> <tr><td>3</td><td>1.4</td><td>2</td><td>20</td><td>4</td><td>51</td></tr> <tr><td>5</td><td>1.1</td><td>3</td><td>21</td><td>6</td><td>52</td></tr> <tr><td>7</td><td>1.8</td><td>4</td><td>20</td><td>8</td><td>53</td></tr></table> <span>A set of time-series data</span> <h4 id="definition-of-path"><a href="#definition-of-path" class="header-anchor">#</a> Definition of Path</h4> <p>A path is a dot-separated string which uniquely identifies a time-series in TsFile, e.g., "root.area_1.device_1.sensor_1". |
| The last section "sensor_1" is called "measurementId" while the remaining parts "root.area_1.device_1" is called deviceId. |
| As mentioned above, the same measurement in different devices has the same data type and encoding, and devices are also unique.</p> <p>In read interfaces, The parameter <code>paths</code> indicates the measurements to be selected.</p> <p>Path instance can be easily constructed through the class <code>Path</code>. For example:</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>Path p = new Path("device_1.sensor_1"); |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p>We will pass an ArrayList of paths for final query call to support multiple paths.</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>List<Path> paths = new ArrayList<Path>(); |
| paths.add(new Path("device_1.sensor_1")); |
| paths.add(new Path("device_1.sensor_3")); |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br></div></div><blockquote><p><strong>Notice:</strong> When constructing a Path, the format of the parameter should be a dot-separated string, the last part will |
| be recognized as measurementId while the remaining parts will be recognized as deviceId.</p></blockquote> <h4 id="definition-of-filter"><a href="#definition-of-filter" class="header-anchor">#</a> Definition of Filter</h4> <h5 id="usage-scenario"><a href="#usage-scenario" class="header-anchor">#</a> Usage Scenario</h5> <p>Filter is used in TsFile reading process to select data satisfying one or more given condition(s).</p> <h4 id="iexpression"><a href="#iexpression" class="header-anchor">#</a> IExpression</h4> <p>The <code>IExpression</code> is a filter expression interface and it will be passed to our final query call. |
| We create one or more filter expressions and may use binary filter operators to link them to our final expression.</p> <ul><li><p><strong>Create a Filter Expression</strong></p> <p>There are two types of filters.</p> <ul><li><p>TimeFilter: A filter for <code>time</code> in time-series data.</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>IExpression timeFilterExpr = new GlobalTimeExpression(TimeFilter); |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p>Use the following relationships to get a <code>TimeFilter</code> object (value is a long int variable). |
| <center><table style="text-align:center;"><tr><th>Relationship</th><th>Description</th></tr> <tr><td>TimeFilter.eq(value)</td><td>Choose the time equal to the value</td></tr> <tr><td>TimeFilter.lt(value)</td><td>Choose the time less than the value</td></tr> <tr><td>TimeFilter.gt(value)</td><td>Choose the time greater than the value</td></tr> <tr><td>TimeFilter.ltEq(value)</td><td>Choose the time less than or equal to the value</td></tr> <tr><td>TimeFilter.gtEq(value)</td><td>Choose the time greater than or equal to the value</td></tr> <tr><td>TimeFilter.notEq(value)</td><td>Choose the time not equal to the value</td></tr> <tr><td>TimeFilter.not(TimeFilter)</td><td>Choose the time not satisfy another TimeFilter</td></tr></table></center></p></li> <li><p>ValueFilter: A filter for <code>value</code> in time-series data.</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>IExpression valueFilterExpr = new SingleSeriesExpression(Path, ValueFilter); |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p>The usage of <code>ValueFilter</code> is the same as using <code>TimeFilter</code>, just to make sure that the type of the value |
| equal to the measurement's(defined in the path).</p></li></ul></li> <li><p><strong>Binary Filter Operators</strong></p> <p>Binary filter operators can be used to link two single expressions.</p> <ul><li>BinaryExpression.and(Expression, Expression): Choose the value satisfy for both expressions.</li> <li>BinaryExpression.or(Expression, Expression): Choose the value satisfy for at least one expression.</li></ul></li></ul> <h5 id="filter-expression-examples"><a href="#filter-expression-examples" class="header-anchor">#</a> Filter Expression Examples</h5> <ul><li><p><strong>TimeFilterExpression Examples</strong></p> <div class="language- line-numbers-mode"><pre class="language-text"><code>IExpression timeFilterExpr = new GlobalTimeExpression(TimeFilter.eq(15)); // series time = 15 |
| |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><div class="language- line-numbers-mode"><pre class="language-text"><code>IExpression timeFilterExpr = new GlobalTimeExpression(TimeFilter.ltEq(15)); // series time <= 15 |
| |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><div class="language- line-numbers-mode"><pre class="language-text"><code>IExpression timeFilterExpr = new GlobalTimeExpression(TimeFilter.lt(15)); // series time < 15 |
| |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><div class="language- line-numbers-mode"><pre class="language-text"><code>IExpression timeFilterExpr = new GlobalTimeExpression(TimeFilter.gtEq(15)); // series time >= 15 |
| |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><div class="language- line-numbers-mode"><pre class="language-text"><code>IExpression timeFilterExpr = new GlobalTimeExpression(TimeFilter.notEq(15)); // series time != 15 |
| |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><div class="language- line-numbers-mode"><pre class="language-text"><code>IExpression timeFilterExpr = BinaryExpression.and(new GlobalTimeExpression(TimeFilter.gtEq(15L)), |
| new GlobalTimeExpression(TimeFilter.lt(25L))); // 15 <= series time < 25 |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><div class="language- line-numbers-mode"><pre class="language-text"><code>IExpression timeFilterExpr = BinaryExpression.or(new GlobalTimeExpression(TimeFilter.gtEq(15L)), |
| new GlobalTimeExpression(TimeFilter.lt(25L))); // series time >= 15 or series time < 25 |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div></li></ul> <h4 id="read-interface"><a href="#read-interface" class="header-anchor">#</a> Read Interface</h4> <p>First, we open the TsFile and get a <code>ReadOnlyTsFile</code> instance from a file path string <code>path</code>.</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>TsFileSequenceReader reader = new TsFileSequenceReader(path); |
| |
| ReadOnlyTsFile readTsFile = new ReadOnlyTsFile(reader); |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br></div></div><p>Next, we prepare the path array and query expression, then get final <code>QueryExpression</code> object by this interface:</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>QueryExpression queryExpression = QueryExpression.create(paths, statement); |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p>The ReadOnlyTsFile class has two <code>query</code> method to perform a query.</p> <ul><li><p><strong>Method 1</strong></p> <div class="language- line-numbers-mode"><pre class="language-text"><code>public QueryDataSet query(QueryExpression queryExpression) throws IOException |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div></li> <li><p><strong>Method 2</strong></p> <div class="language- line-numbers-mode"><pre class="language-text"><code>public QueryDataSet query(QueryExpression queryExpression, long partitionStartOffset, long partitionEndOffset) throws IOException |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p>This method is designed for advanced applications such as the TsFile-Spark Connector.</p> <ul><li><p><strong>params</strong> : For method 2, two additional parameters are added to support partial query:</p> <ul><li><code>partitionStartOffset</code>: start offset for a TsFile</li> <li><code>partitionEndOffset</code>: end offset for a TsFile</li></ul> <blockquote><p><strong>What is Partial Query ?</strong></p> <p>In some distributed file systems(e.g. HDFS), a file is split into severval parts which are called "Blocks" and stored in different nodes. Executing a query paralleled in each nodes involved makes better efficiency. Thus Partial Query is needed. Paritial Query only selects the results stored in the part split by <code>QueryConstant.PARTITION_START_OFFSET</code> and <code>QueryConstant.PARTITION_END_OFFSET</code> for a TsFile.</p></blockquote></li></ul></li></ul> <h3 id="querydataset-interface"><a href="#querydataset-interface" class="header-anchor">#</a> QueryDataset Interface</h3> <p>The query performed above will return a <code>QueryDataset</code> object.</p> <p>Here's the useful interfaces for user.</p> <ul><li><p><code>bool hasNext();</code></p> <p>Return true if this dataset still has elements.</p></li> <li><p><code>List<Path> getPaths()</code></p> <p>Get the paths in this data set.</p></li> <li><p><code>List<TSDataType> getDataTypes();</code></p> <p>Get the data types. The class TSDataType is an enum class, the value will be one of the following:</p> <div class="language- extra-class"><pre><code> BOOLEAN, |
| INT32, |
| INT64, |
| FLOAT, |
| DOUBLE, |
| TEXT; |
| </code></pre></div></li> <li><p><code>RowRecord next() throws IOException;</code></p> <p>Get the next record.</p> <p>The class <code>RowRecord</code> consists of a <code>long</code> timestamp and a <code>List<Field></code> for data in different sensors, |
| we can use two getter methods to get them.</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>long getTimestamp(); |
| List<Field> getFields(); |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><p>To get data from one Field, use these methods:</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>TSDataType getDataType(); |
| Object getObjectValue(); |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div></li></ul> <h4 id="example-for-reading-an-existing-tsfile"><a href="#example-for-reading-an-existing-tsfile" class="header-anchor">#</a> Example for reading an existing TsFile</h4> <p>You should install TsFile to your local maven repository.</p> <p>A more thorough example with query statement can be found at |
| <code>/tsfile/example/src/main/java/org/apache/iotdb/tsfile/TsFileRead.java</code></p> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">java<span class="token punctuation">.</span>io</span><span class="token punctuation">.</span><span class="token class-name">IOException</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">java<span class="token punctuation">.</span>util</span><span class="token punctuation">.</span><span class="token class-name">ArrayList</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>read</span><span class="token punctuation">.</span><span class="token class-name">ReadOnlyTsFile</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>read</span><span class="token punctuation">.</span><span class="token class-name">TsFileSequenceReader</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>read<span class="token punctuation">.</span>common</span><span class="token punctuation">.</span><span class="token class-name">Path</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>read<span class="token punctuation">.</span>expression</span><span class="token punctuation">.</span><span class="token class-name">IExpression</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>read<span class="token punctuation">.</span>expression</span><span class="token punctuation">.</span><span class="token class-name">QueryExpression</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>read<span class="token punctuation">.</span>expression<span class="token punctuation">.</span>impl</span><span class="token punctuation">.</span><span class="token class-name">BinaryExpression</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>read<span class="token punctuation">.</span>expression<span class="token punctuation">.</span>impl</span><span class="token punctuation">.</span><span class="token class-name">GlobalTimeExpression</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>read<span class="token punctuation">.</span>expression<span class="token punctuation">.</span>impl</span><span class="token punctuation">.</span><span class="token class-name">SingleSeriesExpression</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>read<span class="token punctuation">.</span>filter</span><span class="token punctuation">.</span><span class="token class-name">TimeFilter</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>read<span class="token punctuation">.</span>filter</span><span class="token punctuation">.</span><span class="token class-name">ValueFilter</span><span class="token punctuation">;</span> |
| <span class="token keyword">import</span> <span class="token namespace">org<span class="token punctuation">.</span>apache<span class="token punctuation">.</span>iotdb<span class="token punctuation">.</span>tsfile<span class="token punctuation">.</span>read<span class="token punctuation">.</span>query<span class="token punctuation">.</span>dataset</span><span class="token punctuation">.</span><span class="token class-name">QueryDataSet</span><span class="token punctuation">;</span> |
| |
| <span class="token comment">/** |
| * The class is to show how to read TsFile file named "test.tsfile". |
| * The TsFile file "test.tsfile" is generated from class TsFileWrite. |
| * Run TsFileWrite to generate the test.tsfile first |
| */</span> |
| <span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">TsFileRead</span> <span class="token punctuation">{</span> |
| <span class="token keyword">private</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">queryAndPrint</span><span class="token punctuation">(</span><span class="token class-name">ArrayList</span><span class="token generics"><span class="token punctuation"><</span><span class="token class-name">Path</span><span class="token punctuation">></span></span> paths<span class="token punctuation">,</span> <span class="token class-name">ReadOnlyTsFile</span> readTsFile<span class="token punctuation">,</span> <span class="token class-name">IExpression</span> statement<span class="token punctuation">)</span> |
| <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span> |
| <span class="token class-name">QueryExpression</span> queryExpression <span class="token operator">=</span> <span class="token class-name">QueryExpression</span><span class="token punctuation">.</span><span class="token function">create</span><span class="token punctuation">(</span>paths<span class="token punctuation">,</span> statement<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token class-name">QueryDataSet</span> queryDataSet <span class="token operator">=</span> readTsFile<span class="token punctuation">.</span><span class="token function">query</span><span class="token punctuation">(</span>queryExpression<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token keyword">while</span> <span class="token punctuation">(</span>queryDataSet<span class="token punctuation">.</span><span class="token function">hasNext</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> |
| <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">println</span><span class="token punctuation">(</span>queryDataSet<span class="token punctuation">.</span><span class="token function">next</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> |
| <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">println</span><span class="token punctuation">(</span><span class="token string">"------------"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> |
| |
| <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span> |
| |
| <span class="token comment">// file path</span> |
| <span class="token class-name">String</span> path <span class="token operator">=</span> <span class="token string">"test.tsfile"</span><span class="token punctuation">;</span> |
| |
| <span class="token comment">// create reader and get the readTsFile interface</span> |
| <span class="token class-name">TsFileSequenceReader</span> reader <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">TsFileSequenceReader</span><span class="token punctuation">(</span>path<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token class-name">ReadOnlyTsFile</span> readTsFile <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">ReadOnlyTsFile</span><span class="token punctuation">(</span>reader<span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token comment">// use these paths(all sensors) for all the queries</span> |
| <span class="token class-name">ArrayList</span><span class="token generics"><span class="token punctuation"><</span><span class="token class-name">Path</span><span class="token punctuation">></span></span> paths <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">ArrayList</span><span class="token generics"><span class="token punctuation"><</span><span class="token punctuation">></span></span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| paths<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">Path</span><span class="token punctuation">(</span><span class="token string">"device_1.sensor_1"</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| paths<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">Path</span><span class="token punctuation">(</span><span class="token string">"device_1.sensor_2"</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| paths<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">Path</span><span class="token punctuation">(</span><span class="token string">"device_1.sensor_3"</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| |
| <span class="token comment">// no query statement</span> |
| <span class="token function">queryAndPrint</span><span class="token punctuation">(</span>paths<span class="token punctuation">,</span> readTsFile<span class="token punctuation">,</span> <span class="token keyword">null</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| |
| <span class="token comment">//close the reader when you left</span> |
| reader<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> |
| <span class="token punctuation">}</span> |
| <span class="token punctuation">}</span> |
| |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br><span class="line-number">36</span><br><span class="line-number">37</span><br><span class="line-number">38</span><br><span class="line-number">39</span><br><span class="line-number">40</span><br><span class="line-number">41</span><br><span class="line-number">42</span><br><span class="line-number">43</span><br><span class="line-number">44</span><br><span class="line-number">45</span><br><span class="line-number">46</span><br><span class="line-number">47</span><br><span class="line-number">48</span><br><span class="line-number">49</span><br><span class="line-number">50</span><br><span class="line-number">51</span><br><span class="line-number">52</span><br><span class="line-number">53</span><br></div></div><h2 id="change-tsfile-config"><a href="#change-tsfile-config" class="header-anchor">#</a> Change TsFile Config</h2> <div class="language- line-numbers-mode"><pre class="language-text"><code>TSFileConfig config = TSFileDescriptor.getInstance().getConfig(); |
| config.setXXX(); |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><h2 id="bloom-filter"><a href="#bloom-filter" class="header-anchor">#</a> Bloom filter</h2> <p>Bloom filter checks whether a given time series is in the tsfile before loading metadata. This can improve the performance of loading metadata and skip the tsfile that doesn't contain specified time series. |
| If you want to learn more about its mechanism, you can refer to: <a href="https://en.wikipedia.org/wiki/Bloom_filter" target="_blank" rel="noopener noreferrer">wiki page of bloom filter<svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></a>.</p> <h4 id="configuration"><a href="#configuration" class="header-anchor">#</a> configuration</h4> <p>you can control the false positive rate of bloom filter by changing the bloomFilterErrorRate in TSFileConfig</p> <div class="language- line-numbers-mode"><pre class="language-text"><code># The acceptable error rate of bloom filter, should be in [0.01, 0.1], default is 0.05 |
| bloomFilterErrorRate=0.05 |
| </code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div></div> <div class="page-nav"><p class="inner"><span class="prev"> |
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| Apache and the Apache feather logo are trademarks of The Apache Software Foundation</p> <p style="text-align:justify!important;paddingLeft:10px;paddingRight:10px;"> |
| Disclaimer: Apache IoTDB (incubating) is an effort undergoing incubation at The Apache Software Foundation (ASF), sponsored by the Apache Incubator. Incubation is required of all newly accepted projects until a further review indicates that the infrastructure, communications, and decision making process have stabilized in a manner consistent with other successful ASF projects. While incubation status is not necessarily a reflection of the completeness or stability of the code, it does indicate that the project has yet to be fully endorsed by the ASF. |
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