integration/hive/hive-guide.md

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# Quick Start
This tutorial provides a quick introduction to using current integration/hive module.

## Build (In 1.2.0, hive integration only support spark2.1 and hadoop2.7.2)
mvn -DskipTests -Pspark-2.1 -Phadoop-2.7.2 clean package

## Prepare CarbonData in Spark
* Create a sample.csv file using the following commands. The CSV file is required for loading data into CarbonData.

  ```
  cd carbondata
  cat > sample.csv << EOF
  id,name,scale,country,salary
  1,yuhai,1.77,china,33000.1
  2,runlin,1.70,china,33000.2
  EOF
  ```

* copy data to HDFS

```
$HADOOP_HOME/bin/hadoop fs -put sample.csv <hdfs store path>/sample.csv
```

* Add the following params to $SPARK_CONF_DIR/conf/hive-site.xml
```xml
<property>
  <name>hive.metastore.pre.event.listeners</name>
  <value>org.apache.carbondata.hive.CarbonHiveMetastoreListener</value>
</property>
```
* Start Spark shell by running the following command in the Spark directory

```
./bin/spark-shell --jars <carbondata assembly jar path, carbon hive jar path>
```

```
import org.apache.spark.sql.SparkSession
import org.apache.spark.sql.CarbonSession._
val rootPath = "hdfs:////user/hadoop/carbon"
val storeLocation = s"$rootPath/store"
val warehouse = s"$rootPath/warehouse"
val metastoredb = s"$rootPath/metastore_db"

val carbon = SparkSession.builder().enableHiveSupport().config("spark.sql.warehouse.dir", warehouse).config(org.apache.carbondata.core.constants.CarbonCommonConstants.STORE_LOCATION, storeLocation).getOrCreateCarbonSession(storeLocation, metastoredb)

carbon.sql("create table hive_carbon(id int, name string, scale decimal, country string, salary double) STORED BY 'carbondata'")
carbon.sql("LOAD DATA INPATH '<hdfs store path>/sample.csv' INTO TABLE hive_carbon")
scala>carbon.sql("SELECT * FROM hive_carbon").show()
```

## Query Data in Hive
### Configure hive classpath
```
mkdir hive/auxlibs/
cp carbondata/assembly/target/scala-2.11/carbondata_2.11*.jar hive/auxlibs/
cp carbondata/integration/hive/target/carbondata-hive-*.jar hive/auxlibs/
cp $SPARK_HOME/jars/spark-catalyst*.jar hive/auxlibs/
cp $SPARK_HOME/jars/scala*.jar hive/auxlibs/
export HIVE_AUX_JARS_PATH=hive/auxlibs/
```
### Fix snappy issue
```
copy snappy-java-xxx.jar from "./<SPARK_HOME>/jars/" to "./Library/Java/Extensions"
export HADOOP_OPTS="-Dorg.xerial.snappy.lib.path=/Library/Java/Extensions -Dorg.xerial.snappy.lib.name=libsnappyjava.jnilib -Dorg.xerial.snappy.tempdir=/Users/apple/DEMO/tmp"
```

### Start hive client
$HIVE_HOME/bin/hive

### Query data from hive table

```
set hive.mapred.supports.subdirectories=true;
set mapreduce.input.fileinputformat.input.dir.recursive=true;

select * from hive_carbon;
select count(*) from hive_carbon;
select * from hive_carbon order by id;
```