Metadata (System Tables)

Exasol disposes of numerous system tables, which describe the metadata of the database and the current status of the system. These system tables are located in the "SYS" and "EXA_STATISTICS" schemas and are integrated automatically into the current namespace. Therefore, if an object with the same name does not exist in the current schema, then it can be queried without stating the schema name, "SYS". Otherwise, you can access the system tables through the respective schema-qualified name, SYS.<table_name> (for example, SELECT * FROM SYS.DUAL).

Some system tables are critical to the security. You can access these tables with the SELECT ANY DICTIONARY system privilege (users with the DBA role have this privilege implicitly). It includes all system tables with the EXA_DBA_ prefix.

There are also system tables to which everyone has access. However, the content of these tables is dependent on the current user. In EXA_ALL_OBJECTS, for example, only the database objects the current user has access to are displayed.

The system tables supported in Exasol including their access rules are described in the following sections: