IoTDB具备Java原生客户端驱动和对应的连接池，提供对象化接口，可以直接组装时序对象进行写入，无需拼装 SQL。推荐使用连接池，多线程并行操作数据库。
环境要求:
在maven中添加依赖:
<dependencies> <dependency> <groupId>com.timecho.iotdb</groupId> <artifactId>iotdb-session</artifactId> <version>2.0.1.1</version> </dependency> </dependencies>
ITableSession接口定义了与IoTDB交互的基本操作，可以执行数据插入、查询操作以及关闭会话等，非线程安全。
以下是ITableSession接口中定义的方法及其详细说明：
| 方法名 | 描述 | 参数 | 返回值 | 返回异常 |
|---|---|---|---|---|
| insert(Tablet tablet) | 将一个包含时间序列数据的Tablet 对象插入到数据库中 | tablet: 要插入的Tablet对象 | 无 | StatementExecutionExceptionIoTDBConnectionException |
| executeNonQueryStatement(String sql) | 执行非查询SQL语句，如DDL(数据定义语言)或DML(数据操作语言）命令 | sql: 要执行的SQL语句。 | 无 | StatementExecutionExceptionIoTDBConnectionException |
| executeQueryStatement(String sql) | 执行查询SQL语句，并返回包含查询结果的SessionDataSet对象 | sql: 要执行的查询SQL语句。 | SessionDataSet | StatementExecutionExceptionIoTDBConnectionException |
| executeQueryStatement(String sql, long timeoutInMs) | 执行查询SQL语句，并设置查询超时时间（以毫秒为单位） | sql: 要执行的查询SQL语句。timeoutInMs: 查询超时时间（毫秒） | SessionDataSet | StatementExecutionException |
| close() | 关闭会话，释放所持有的资源 | 无 | 无 | IoTDBConnectionException |
/** * This interface defines a session for interacting with IoTDB tables. * It supports operations such as data insertion, executing queries, and closing the session. * Implementations of this interface are expected to manage connections and ensure * proper resource cleanup. * * <p>Each method may throw exceptions to indicate issues such as connection errors or * execution failures. * * <p>Since this interface extends {@link AutoCloseable}, it is recommended to use * try-with-resources to ensure the session is properly closed. */ public interface ITableSession extends AutoCloseable { /** * Inserts a {@link Tablet} into the database. * * @param tablet the tablet containing time-series data to be inserted. * @throws StatementExecutionException if an error occurs while executing the statement. * @throws IoTDBConnectionException if there is an issue with the IoTDB connection. */ void insert(Tablet tablet) throws StatementExecutionException, IoTDBConnectionException; /** * Executes a non-query SQL statement, such as a DDL or DML command. * * @param sql the SQL statement to execute. * @throws IoTDBConnectionException if there is an issue with the IoTDB connection. * @throws StatementExecutionException if an error occurs while executing the statement. */ void executeNonQueryStatement(String sql) throws IoTDBConnectionException, StatementExecutionException; /** * Executes a query SQL statement and returns the result set. * * @param sql the SQL query statement to execute. * @return a {@link SessionDataSet} containing the query results. * @throws StatementExecutionException if an error occurs while executing the statement. * @throws IoTDBConnectionException if there is an issue with the IoTDB connection. */ SessionDataSet executeQueryStatement(String sql) throws StatementExecutionException, IoTDBConnectionException; /** * Executes a query SQL statement with a specified timeout and returns the result set. * * @param sql the SQL query statement to execute. * @param timeoutInMs the timeout duration in milliseconds for the query execution. * @return a {@link SessionDataSet} containing the query results. * @throws StatementExecutionException if an error occurs while executing the statement. * @throws IoTDBConnectionException if there is an issue with the IoTDB connection. */ SessionDataSet executeQueryStatement(String sql, long timeoutInMs) throws StatementExecutionException, IoTDBConnectionException; /** * Closes the session, releasing any held resources. * * @throws IoTDBConnectionException if there is an issue with closing the IoTDB connection. */ @Override void close() throws IoTDBConnectionException; }
TableSessionBuilder类是一个构建器，用于配置和创建ITableSession接口的实例。它允许开发者设置连接参数、查询参数和安全特性等。
以下是TableSessionBuilder类中可用的配置选项及其默认值：
| 配置项 | 描述 | 默认值 |
|---|---|---|
nodeUrls(List<String> nodeUrls) | 设置IoTDB集群的节点URL列表 | Collections.singletonList(“localhost:6667”) |
| username(String username) | 设置连接的用户名 | “root” |
| password(String password) | 设置连接的密码 | “TimechoDB@2021” //V2.0.6.x 之前默认密码是root |
| database(String database) | 设置目标数据库名称 | null |
| queryTimeoutInMs(long queryTimeoutInMs) | 设置查询超时时间（毫秒） | 60000（1分钟） |
| fetchSize(int fetchSize) | 设置查询结果的获取大小 | 5000 |
| zoneId(ZoneId zoneId) | 设置时区相关的ZoneId | ZoneId.systemDefault() |
| thriftDefaultBufferSize(int thriftDefaultBufferSize) | 设置Thrift客户端的默认缓冲区大小（字节） | 1024（1KB） |
| thriftMaxFrameSize(int thriftMaxFrameSize) | 设置Thrift客户端的最大帧大小（字节） | 64 * 1024 * 1024（64MB） |
| enableRedirection(boolean enableRedirection) | 是否启用集群节点的重定向 | true |
| enableAutoFetch(boolean enableAutoFetch) | 是否启用自动获取可用DataNodes | true |
| maxRetryCount(int maxRetryCount) | 设置连接尝试的最大重试次数 | 60 |
| retryIntervalInMs(long retryIntervalInMs) | 设置重试间隔时间（毫秒） | 500 |
| useSSL(boolean useSSL) | 是否启用SSL安全连接 | false |
| trustStore(String keyStore) | 设置SSL连接的信任库路径 | null |
| trustStorePwd(String keyStorePwd) | 设置SSL连接的信任库密码 | null |
| enableCompression(boolean enableCompression) | 是否启用RPC压缩 | false |
| connectionTimeoutInMs(int connectionTimeoutInMs) | 设置连接超时时间（毫秒） | 0（无超时） |
/** * A builder class for constructing instances of {@link ITableSession}. * * <p>This builder provides a fluent API for configuring various options such as connection * settings, query parameters, and security features. * * <p>All configurations have reasonable default values, which can be overridden as needed. */ public class TableSessionBuilder { /** * Builds and returns a configured {@link ITableSession} instance. * * @return a fully configured {@link ITableSession}. * @throws IoTDBConnectionException if an error occurs while establishing the connection. */ public ITableSession build() throws IoTDBConnectionException; /** * Sets the list of node URLs for the IoTDB cluster. * * @param nodeUrls a list of node URLs. * @return the current {@link TableSessionBuilder} instance. * @defaultValue Collection.singletonList("localhost:6667") */ public TableSessionBuilder nodeUrls(List<String> nodeUrls); /** * Sets the username for the connection. * * @param username the username. * @return the current {@link TableSessionBuilder} instance. * @defaultValue "root“ */ public TableSessionBuilder username(String username); /** * Sets the password for the connection. * * @param password the password. * @return the current {@link TableSessionBuilder} instance. * @defaultValue "TimechoDB@2021" //V2.0.6.x 之前默认密码是root */ public TableSessionBuilder password(String password); /** * Sets the target database name. * * @param database the database name. * @return the current {@link TableSessionBuilder} instance. * @defaultValue null */ public TableSessionBuilder database(String database); /** * Sets the query timeout in milliseconds. * * @param queryTimeoutInMs the query timeout in milliseconds. * @return the current {@link TableSessionBuilder} instance. * @defaultValue 60000 (1 minute) */ public TableSessionBuilder queryTimeoutInMs(long queryTimeoutInMs); /** * Sets the fetch size for query results. * * @param fetchSize the fetch size. * @return the current {@link TableSessionBuilder} instance. * @defaultValue 5000 */ public TableSessionBuilder fetchSize(int fetchSize); /** * Sets the {@link ZoneId} for timezone-related operations. * * @param zoneId the {@link ZoneId}. * @return the current {@link TableSessionBuilder} instance. * @defaultValue ZoneId.systemDefault() */ public TableSessionBuilder zoneId(ZoneId zoneId); /** * Sets the default init buffer size for the Thrift client. * * @param thriftDefaultBufferSize the buffer size in bytes. * @return the current {@link TableSessionBuilder} instance. * @defaultValue 1024 (1 KB) */ public TableSessionBuilder thriftDefaultBufferSize(int thriftDefaultBufferSize); /** * Sets the maximum frame size for the Thrift client. * * @param thriftMaxFrameSize the maximum frame size in bytes. * @return the current {@link TableSessionBuilder} instance. * @defaultValue 64 * 1024 * 1024 (64 MB) */ public TableSessionBuilder thriftMaxFrameSize(int thriftMaxFrameSize); /** * Enables or disables redirection for cluster nodes. * * @param enableRedirection whether to enable redirection. * @return the current {@link TableSessionBuilder} instance. * @defaultValue true */ public TableSessionBuilder enableRedirection(boolean enableRedirection); /** * Enables or disables automatic fetching of available DataNodes. * * @param enableAutoFetch whether to enable automatic fetching. * @return the current {@link TableSessionBuilder} instance. * @defaultValue true */ public TableSessionBuilder enableAutoFetch(boolean enableAutoFetch); /** * Sets the maximum number of retries for connection attempts. * * @param maxRetryCount the maximum retry count. * @return the current {@link TableSessionBuilder} instance. * @defaultValue 60 */ public TableSessionBuilder maxRetryCount(int maxRetryCount); /** * Sets the interval between retries in milliseconds. * * @param retryIntervalInMs the interval in milliseconds. * @return the current {@link TableSessionBuilder} instance. * @defaultValue 500 milliseconds */ public TableSessionBuilder retryIntervalInMs(long retryIntervalInMs); /** * Enables or disables SSL for secure connections. * * @param useSSL whether to enable SSL. * @return the current {@link TableSessionBuilder} instance. * @defaultValue false */ public TableSessionBuilder useSSL(boolean useSSL); /** * Sets the trust store path for SSL connections. * * @param keyStore the trust store path. * @return the current {@link TableSessionBuilder} instance. * @defaultValue null */ public TableSessionBuilder trustStore(String keyStore); /** * Sets the trust store password for SSL connections. * * @param keyStorePwd the trust store password. * @return the current {@link TableSessionBuilder} instance. * @defaultValue null */ public TableSessionBuilder trustStorePwd(String keyStorePwd); /** * Enables or disables rpc compression for the connection. * * @param enableCompression whether to enable compression. * @return the current {@link TableSessionBuilder} instance. * @defaultValue false */ public TableSessionBuilder enableCompression(boolean enableCompression); /** * Sets the connection timeout in milliseconds. * * @param connectionTimeoutInMs the connection timeout in milliseconds. * @return the current {@link TableSessionBuilder} instance. * @defaultValue 0 (no timeout) */ public TableSessionBuilder connectionTimeoutInMs(int connectionTimeoutInMs); }
注意： 原生API中创建表时，表名或列名中若含有特殊字符或中文字符，无需额外添加双引号括起，否则会包含引号字符。
ITableSessionPool 是一个用于管理 ITableSession实例的池。这个池可以帮助我们高效地重用连接，并且在不需要时正确地清理资源, 该接口定义了如何从池中获取会话以及如何关闭池的基本操作。
| 方法名 | 描述 | 返回值 | 返回异常 |
|---|---|---|---|
| getSession() | 从池中获取一个 ITableSession 实例，用于与 IoTDB 交互。 | ITableSession 实例 | IoTDBConnectionException |
| close() | 关闭会话池，释放任何持有的资源。关闭后，不能再从池中获取新的会话。 | 无 | 无 |
/** * This interface defines a pool for managing {@link ITableSession} instances. * It provides methods to acquire a session from the pool and to close the pool. * * <p>The implementation should handle the lifecycle of sessions, ensuring efficient * reuse and proper cleanup of resources. */ public interface ITableSessionPool { /** * Acquires an {@link ITableSession} instance from the pool. * * @return an {@link ITableSession} instance for interacting with the IoTDB. * @throws IoTDBConnectionException if there is an issue obtaining a session from the pool. */ ITableSession getSession() throws IoTDBConnectionException; /** * Closes the session pool, releasing any held resources. * * <p>Once the pool is closed, no further sessions can be acquired. */ void close(); }
TableSessionPool 的构造器，用于配置和创建 ITableSessionPool 的实例。允许开发者配置连接参数、会话参数和池化行为等。
以下是 TableSessionPoolBuilder 类的可用配置选项及其默认值：
| 配置项 | 描述 | 默认值 |
|---|---|---|
nodeUrls(List<String> nodeUrls) | 设置IoTDB集群的节点URL列表 | Collections.singletonList(“localhost:6667”) |
| maxSize(int maxSize) | 设置会话池的最大大小，即池中允许的最大会话数 | 5 |
| user(String user) | 设置连接的用户名 | “root” |
| password(String password) | 设置连接的密码 | “TimechoDB@2021” //V2.0.6.x 之前默认密码是root |
| database(String database) | 设置目标数据库名称 | “root” |
| queryTimeoutInMs(long queryTimeoutInMs) | 设置查询超时时间（毫秒） | 60000（1分钟） |
| fetchSize(int fetchSize) | 设置查询结果的获取大小 | 5000 |
| zoneId(ZoneId zoneId) | 设置时区相关的 ZoneId | ZoneId.systemDefault() |
| waitToGetSessionTimeoutInMs(long waitToGetSessionTimeoutInMs) | 设置从池中获取会话的超时时间（毫秒） | 30000（30秒） |
| thriftDefaultBufferSize(int thriftDefaultBufferSize) | 设置Thrift客户端的默认缓冲区大小（字节） | 1024（1KB） |
| thriftMaxFrameSize(int thriftMaxFrameSize) | 设置Thrift客户端的最大帧大小（字节） | 64 * 1024 * 1024（64MB） |
| enableCompression(boolean enableCompression) | 是否启用连接的压缩 | false |
| enableRedirection(boolean enableRedirection) | 是否启用集群节点的重定向 | true |
| connectionTimeoutInMs(int connectionTimeoutInMs) | 设置连接超时时间（毫秒） | 10000（10秒） |
| enableAutoFetch(boolean enableAutoFetch) | 是否启用自动获取可用DataNodes | true |
| maxRetryCount(int maxRetryCount) | 设置连接尝试的最大重试次数 | 60 |
| retryIntervalInMs(long retryIntervalInMs) | 设置重试间隔时间（毫秒） | 500 |
| useSSL(boolean useSSL) | 是否启用SSL安全连接 | false |
| trustStore(String keyStore) | 设置SSL连接的信任库路径 | null |
| trustStorePwd(String keyStorePwd) | 设置SSL连接的信任库密码 | null |
/** * A builder class for constructing instances of {@link ITableSessionPool}. * * <p>This builder provides a fluent API for configuring a session pool, including * connection settings, session parameters, and pool behavior. * * <p>All configurations have reasonable default values, which can be overridden as needed. */ public class TableSessionPoolBuilder { /** * Builds and returns a configured {@link ITableSessionPool} instance. * * @return a fully configured {@link ITableSessionPool}. */ public ITableSessionPool build(); /** * Sets the list of node URLs for the IoTDB cluster. * * @param nodeUrls a list of node URLs. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue Collection.singletonList("localhost:6667") */ public TableSessionPoolBuilder nodeUrls(List<String> nodeUrls); /** * Sets the maximum size of the session pool. * * @param maxSize the maximum number of sessions allowed in the pool. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue 5 */ public TableSessionPoolBuilder maxSize(int maxSize); /** * Sets the username for the connection. * * @param user the username. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue "root" */ public TableSessionPoolBuilder user(String user); /** * Sets the password for the connection. * * @param password the password. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue "TimechoDB@2021" //V2.0.6.x 之前默认密码是root */ public TableSessionPoolBuilder password(String password); /** * Sets the target database name. * * @param database the database name. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue "root" */ public TableSessionPoolBuilder database(String database); /** * Sets the query timeout in milliseconds. * * @param queryTimeoutInMs the query timeout in milliseconds. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue 60000 (1 minute) */ public TableSessionPoolBuilder queryTimeoutInMs(long queryTimeoutInMs); /** * Sets the fetch size for query results. * * @param fetchSize the fetch size. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue 5000 */ public TableSessionPoolBuilder fetchSize(int fetchSize); /** * Sets the {@link ZoneId} for timezone-related operations. * * @param zoneId the {@link ZoneId}. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue ZoneId.systemDefault() */ public TableSessionPoolBuilder zoneId(ZoneId zoneId); /** * Sets the timeout for waiting to acquire a session from the pool. * * @param waitToGetSessionTimeoutInMs the timeout duration in milliseconds. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue 30000 (30 seconds) */ public TableSessionPoolBuilder waitToGetSessionTimeoutInMs(long waitToGetSessionTimeoutInMs); /** * Sets the default buffer size for the Thrift client. * * @param thriftDefaultBufferSize the buffer size in bytes. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue 1024 (1 KB) */ public TableSessionPoolBuilder thriftDefaultBufferSize(int thriftDefaultBufferSize); /** * Sets the maximum frame size for the Thrift client. * * @param thriftMaxFrameSize the maximum frame size in bytes. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue 64 * 1024 * 1024 (64 MB) */ public TableSessionPoolBuilder thriftMaxFrameSize(int thriftMaxFrameSize); /** * Enables or disables compression for the connection. * * @param enableCompression whether to enable compression. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue false */ public TableSessionPoolBuilder enableCompression(boolean enableCompression); /** * Enables or disables redirection for cluster nodes. * * @param enableRedirection whether to enable redirection. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue true */ public TableSessionPoolBuilder enableRedirection(boolean enableRedirection); /** * Sets the connection timeout in milliseconds. * * @param connectionTimeoutInMs the connection timeout in milliseconds. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue 10000 (10 seconds) */ public TableSessionPoolBuilder connectionTimeoutInMs(int connectionTimeoutInMs); /** * Enables or disables automatic fetching of available DataNodes. * * @param enableAutoFetch whether to enable automatic fetching. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue true */ public TableSessionPoolBuilder enableAutoFetch(boolean enableAutoFetch); /** * Sets the maximum number of retries for connection attempts. * * @param maxRetryCount the maximum retry count. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue 60 */ public TableSessionPoolBuilder maxRetryCount(int maxRetryCount); /** * Sets the interval between retries in milliseconds. * * @param retryIntervalInMs the interval in milliseconds. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue 500 milliseconds */ public TableSessionPoolBuilder retryIntervalInMs(long retryIntervalInMs); /** * Enables or disables SSL for secure connections. * * @param useSSL whether to enable SSL. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue false */ public TableSessionPoolBuilder useSSL(boolean useSSL); /** * Sets the trust store path for SSL connections. * * @param keyStore the trust store path. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue null */ public TableSessionPoolBuilder trustStore(String keyStore); /** * Sets the trust store password for SSL connections. * * @param keyStorePwd the trust store password. * @return the current {@link TableSessionPoolBuilder} instance. * @defaultValue null */ public TableSessionPoolBuilder trustStorePwd(String keyStorePwd); }
Session 示例代码：src/main/java/org/apache/iotdb/TableModelSessionExample.java
SessionPool 示例代码：src/main/java/org/apache/iotdb/TableModelSessionPoolExample.java
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ package org.apache.iotdb; import org.apache.iotdb.isession.ITableSession; import org.apache.iotdb.isession.SessionDataSet; import org.apache.iotdb.isession.pool.ITableSessionPool; import org.apache.iotdb.rpc.IoTDBConnectionException; import org.apache.iotdb.rpc.StatementExecutionException; import org.apache.iotdb.session.pool.TableSessionPoolBuilder; import org.apache.tsfile.enums.ColumnCategory; import org.apache.tsfile.enums.TSDataType; import org.apache.tsfile.write.record.Tablet; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.List; import static org.apache.iotdb.SessionExample.printDataSet; public class TableModelSessionPoolExample { private static final String LOCAL_URL = "127.0.0.1:6667"; public static void main(String[] args) { // don't specify database in constructor ITableSessionPool tableSessionPool = new TableSessionPoolBuilder() .nodeUrls(Collections.singletonList(LOCAL_URL)) .user("root") .password("TimechoDB@2021") //V2.0.6.x 之前默认密码是root .maxSize(1) .build(); try (ITableSession session = tableSessionPool.getSession()) { session.executeNonQueryStatement("CREATE DATABASE test1"); session.executeNonQueryStatement("CREATE DATABASE test2"); session.executeNonQueryStatement("use test2"); // or use full qualified table name session.executeNonQueryStatement( "create table test1.table1(" + "region_id STRING TAG, " + "plant_id STRING TAG, " + "device_id STRING TAG, " + "model STRING ATTRIBUTE, " + "temperature FLOAT FIELD, " + "humidity DOUBLE FIELD) with (TTL=3600000)"); session.executeNonQueryStatement( "create table table2(" + "region_id STRING TAG, " + "plant_id STRING TAG, " + "color STRING ATTRIBUTE, " + "temperature FLOAT FIELD, " + "speed DOUBLE FIELD) with (TTL=6600000)"); // show tables from current database try (SessionDataSet dataSet = session.executeQueryStatement("SHOW TABLES")) { printDataSet(dataSet); } // show tables by specifying another database // using SHOW tables FROM try (SessionDataSet dataSet = session.executeQueryStatement("SHOW TABLES FROM test1")) { printDataSet(dataSet); } // insert table data by tablet List<String> columnNameList = Arrays.asList("region_id", "plant_id", "device_id", "model", "temperature", "humidity"); List<TSDataType> dataTypeList = Arrays.asList( TSDataType.STRING, TSDataType.STRING, TSDataType.STRING, TSDataType.STRING, TSDataType.FLOAT, TSDataType.DOUBLE); List<ColumnCategory> columnTypeList = new ArrayList<>( Arrays.asList( ColumnCategory.TAG, ColumnCategory.TAG, ColumnCategory.TAG, ColumnCategory.ATTRIBUTE, ColumnCategory.FIELD, ColumnCategory.FIELD)); Tablet tablet = new Tablet("test1", columnNameList, dataTypeList, columnTypeList, 100); for (long timestamp = 0; timestamp < 100; timestamp++) { int rowIndex = tablet.getRowSize(); tablet.addTimestamp(rowIndex, timestamp); tablet.addValue("region_id", rowIndex, "1"); tablet.addValue("plant_id", rowIndex, "5"); tablet.addValue("device_id", rowIndex, "3"); tablet.addValue("model", rowIndex, "A"); tablet.addValue("temperature", rowIndex, 37.6F); tablet.addValue("humidity", rowIndex, 111.1); if (tablet.getRowSize() == tablet.getMaxRowNumber()) { session.insert(tablet); tablet.reset(); } } if (tablet.getRowSize() != 0) { session.insert(tablet); tablet.reset(); } // query table data try (SessionDataSet dataSet = session.executeQueryStatement( "select * from test1 " + "where region_id = '1' and plant_id in ('3', '5') and device_id = '3'")) { printDataSet(dataSet); } } catch (IoTDBConnectionException e) { e.printStackTrace(); } catch (StatementExecutionException e) { e.printStackTrace(); } finally { tableSessionPool.close(); } // specify database in constructor tableSessionPool = new TableSessionPoolBuilder() .nodeUrls(Collections.singletonList(LOCAL_URL)) .user("root") .password("TimechoDB@2021")//V2.0.6.x 之前默认密码是root .maxSize(1) .database("test1") .build(); try (ITableSession session = tableSessionPool.getSession()) { // show tables from current database try (SessionDataSet dataSet = session.executeQueryStatement("SHOW TABLES")) { printDataSet(dataSet); } // change database to test2 session.executeNonQueryStatement("use test2"); // show tables by specifying another database // using SHOW tables FROM try (SessionDataSet dataSet = session.executeQueryStatement("SHOW TABLES")) { printDataSet(dataSet); } } catch (IoTDBConnectionException e) { e.printStackTrace(); } catch (StatementExecutionException e) { e.printStackTrace(); } try (ITableSession session = tableSessionPool.getSession()) { // show tables from default database test1 try (SessionDataSet dataSet = session.executeQueryStatement("SHOW TABLES")) { printDataSet(dataSet); } } catch (IoTDBConnectionException e) { e.printStackTrace(); } catch (StatementExecutionException e) { e.printStackTrace(); } finally { tableSessionPool.close(); } } }