Catalog Configuration

If you want to customize the catalog service, copy $TAJO_HOME/conf/catalog-site.xml.template to catalog-site.xml. Then, add the following configs to catalog-site.xml. Note that the default configs are enough to launch Tajo cluster in most cases.

  • tajo.catalog.master.addr - If you want to launch a Tajo cluster in distributed mode, you must specify this address. For more detail information, see [Default Ports](#DefaultPorts).
  • tajo.catalog.store.class - If you want to change the persistent storage of the catalog server, specify the class name. Its default value is tajo.catalog.store.DerbyStore. In the current version, Tajo provides three persistent storage classes as follows:
Driver Class Descriptions
tajo.catalog.store.DerbyStore this storage class uses Apache Derby.
tajo.catalog.store.MySQLStore this storage class uses MySQL.
tajo.catalog.store.MariaDBStore this storage class uses MariaDB.
tajo.catalog.store.MemStore this is the in-memory storage. It is only used in unit tests to shorten the duration of unit tests.
tajo.catalog.store.HCatalogStore this storage class uses HiveMetaStore.

Derby Configuration

By default, Tajo uses Apache Derby as a persistent storage in order to manage table meta data. So, without any configuration, you can use Derby for catalog store.

Also, you can set manually configs in conf/catalog-site.xml as follows:

<property>
  <name>tajo.catalog.store.class</name>
  <value>org.apache.tajo.catalog.store.DerbyStore</value>
</property>

<property>
  <name>tajo.catalog.uri</name>
  <value>jdbc:derby:<absolute directory>;create=true</value>
</property>

Since Derby is a file-based embedded database, it stores data into a specified directory. So, you need to specify the directory for storing data files instead of specifying JDBC URI with hostname and port. For example, in case where you use ‘/var/data/tajo-catalog’ as a derby store directory, you should set configs as follows:

<property>
  <name>tajo.catalog.uri</name>
  <value>jdbc:derby:/var/data/tajo-catalog;create=true</value>
</property>

Warning

By default, Catalog server stores catalog data into /tmp/tajo-catalog-${username} directory. But, some operating systems may remove all contents in /tmp when booting up. In order to ensure persistent store of your catalog data, you need to set a proper location of derby directory.

MySQLStore Configuration

In order to use MySQLStore, you need to create database and user on MySQL for Tajo.

mysql> create user 'tajo'@'localhost' identified by 'xxxxxx';
Query OK, 0 rows affected (0.00 sec)

mysql> create database tajo;
Query OK, 1 row affected (0.00 sec)

mysql> grant all on tajo.* to 'tajo'@'localhost';
Query OK, 0 rows affected (0.01 sec)

And then, you need to prepare MySQL JDBC driver on the machine which can be ran TajoMaster. If you do, you should set TAJO_CLASSPATH variable in conf/tajo-env.sh with it as follows:

export TAJO_CLASSPATH=/usr/local/mysql/lib/mysql-connector-java-x.x.x.jar

Or you just can copy jdbc driver into $TAJO_HOME/lib.

Finally, you should add the following config to conf/catalog-site.xml :

<property>
  <name>tajo.catalog.store.class</name>
  <value>org.apache.tajo.catalog.store.MySQLStore</value>
</property>
<property>
  <name>tajo.catalog.jdbc.connection.id</name>
  <value><mysql user name></value>
</property>
<property>
  <name>tajo.catalog.jdbc.connection.password</name>
  <value><mysql user password></value>
</property>
<property>
  <name>tajo.catalog.jdbc.uri</name>
  <value>jdbc:mysql://<mysql host name>:<mysql port>/<database name for tajo>?createDatabaseIfNotExist=true</value>
</property>

MariaDBStore Configuration

All configurations for using MariaDBStore is compatible with MySQLStore except following:

export TAJO_CLASSPATH=/usr/local/mariadb/lib/mariadb-java-client-x.x.x.jar

<property>
  <name>tajo.catalog.store.class</name>
  <value>org.apache.tajo.catalog.store.MariaDBStore</value>
</property>
<property>
  <name>tajo.catalog.jdbc.uri</name>
  <value>jdbc:mariadb://<mariadb host name>:<mariadb port>/<database name for tajo>?createDatabaseIfNotExist=true</value>
</property>

HCatalogStore Configuration

Tajo support HCatalogStore to integrate with hive. If you want to use HCatalogStore, you just do as follows.

First, you must compile source code and get a binary archive as follows:

$ git clone https://git-wip-us.apache.org/repos/asf/tajo.git tajo
$ mvn clean install -DskipTests -Pdist -Dtar -Phcatalog-0.1x.0
$ ls tajo-dist/target/tajo-x.y.z-SNAPSHOT.tar.gz

Currently Tajo supports hive 0.12.0, hive 0.13.0, hive 0.13.1. If you enables HCatalogStore, you set the maven profile as -Phcatalog-0.12.0.

Second, you must set your hive home directory to HIVE_HOME variable in conf/tajo-env.sh with it as follows:

export HIVE_HOME=/path/to/your/hive/directory

Third, if you need to use jdbc to connect HiveMetaStore, you have to prepare mysql jdbc driver on host which can be ran TajoMaster. If you prepare it, you should set jdbc driver file path to HIVE_JDBC_DRIVER_DIR variable in conf/tajo-env.sh with it as follows:

export HIVE_JDBC_DRIVER_DIR=/path/to/your/mysql_jdbc_driver/mysql-connector-java-x.x.x-bin.jar

Lastly, you should add the following config to conf/catalog-site.xml :

<property>
  <name>tajo.catalog.store.class</name>
  <value>org.apache.tajo.catalog.store.HCatalogStore</value>
</property>