Configuring ColumnStore Cross-Engine Joins

You are viewing an old version of this article. View the current version here.

MariaDB ColumnStore allows columnstore tables to be joined with non-columnstore tables (e.g. MyISAM tables) within a query. The non-columnstore table may be on the MariaDB ColumnStore system OR on an external server that supports JDBC connections.

To enable this process, the <CrossEngineSupport> section in Columnstore.xml is configured with JDBC connection information. The following is an example entry in the Columnstore.XML configuration file to gain access to joined tables residing in native MariaDB on the same server as MariaDB ColumnStore:


This change should be made while the ColumnStore server is down. In a multi node deployment, the change should be made on the PM1 node only as this will be replicated to other instances upon restart.

Check here on how to make changes via the command line to Columnstore.xml:


ERROR 1815 (HY000): Internal error: IDB-8001: CrossEngineSupport section in Columnstore.xml is not properly configured

  • Confirm that Columnstore.xml was correctly updated on pm1 and the server restarted.

ERROR 1815 (HY000): Internal error: fatal error in drizzle_con_connect()(23)(23)

  • Confirm that the values specified for CrossEngineSupport in ColumnStore.xml are correct for the login to be used.

ERROR 1815 (HY000): Internal error: fatal error executing query in crossengine client lib(17)(17)

  • Confirm that the login used has create temporary tables permission on infinidb_vtable:
grant create temporary tables on infinidb_vtable.* to [email protected];
  • Confirm that the login used has grants select the table referenced in the cross engine join. Verify by attempting to connect from each UM using mcsmysql and query the table you want to reference:
mcsmysql -u mydbuser -p -h 
> use mydb;
> select * from innodb_table limit 10;


  • Cross engine will not work against a MyISAM/Aria table that has 0 or 1 rows in it. This is due to MariaDB's optimizer shortcut for this specific condition. We recommend using InnoDB instead of MyISAM/Aria for this case.


Comments loading...
Content reproduced on this site is the property of its respective owners, and this content is not reviewed in advance by MariaDB. The views, information and opinions expressed by this content do not necessarily represent those of MariaDB or any other party.