# Derby system tables

Derby includes system tables.

You can query system tables, but you cannot alter them.

All of the above system tables reside in the SYS schema. Because this is not the default schema, qualify all queries accessing the system tables with the SYS schema name.

The recommended way to get more information about these tables is to use an instance of the Java interface java.sql.DatabaseMetaData.

- SYSALIASES system table
  The SYSALIASES table describes the procedures, functions, user-defined types, and user-defined aggregates in the database.
- SYSCHECKS system table
  The SYSCHECKS table describes the check constraints within the current database.
- SYSCOLPERMS system table
  The SYSCOLPERMS table stores the column permissions that have been granted but not revoked.
- SYSCOLUMNS system table
  The SYSCOLUMNS table describes the columns within all tables in the current database.
- SYSCONGLOMERATES system table
  The SYSCONGLOMERATES table describes the conglomerates within the current database. A conglomerate is a unit of storage and is either a table or an index.
- SYSCONSTRAINTS system table
  The SYSCONSTRAINTS table describes the information common to all types of constraints within the current database (currently, this includes primary key, unique, foreign key, and check constraints).
- SYSDEPENDS system table
  The SYSDEPENDS table stores the dependency relationships between persistent objects in the database.
- SYSFILES system table
  The SYSFILES table describes jar files stored in the database.
- SYSFOREIGNKEYS system table
  The SYSFOREIGNKEYS table describes the information specific to foreign key constraints in the current database.
- SYSKEYS system table
  The SYSKEYS table describes the specific information for primary key and unique constraints within the current database.
- SYSPERMS system table
  The SYSPERMS table describes the USAGE permissions for sequence generators, user-defined types, and user-defined aggregates.
- SYSROLES system table
  The SYSROLES table stores the roles in the database.
- SYSROUTINEPERMS system table
  The SYSROUTINEPERMS table stores the permissions that have been granted to routines.
- SYSSCHEMAS system table
  The SYSSCHEMAS table describes the schemas within the current database.
- SYSSEQUENCES system table
  The SYSSEQUENCES table describes the sequence generators in the database.
- SYSSTATEMENTS system table
  The SYSSTATEMENTS table describes the prepared statements in the database.
- SYSSTATISTICS system table
  The SYSSTATISTICS table describes the statistics within the current database.
- SYSTABLEPERMS system table
  The SYSTABLEPERMS table stores the table permissions that have been granted but not revoked.
- SYSTABLES system table
  The SYSTABLES table describes the tables and views within the current database.
- SYSTRIGGERS system table
  The SYSTRIGGERS table describes the database's triggers.
- SYSUSERS system table
  The SYSUSERS table stores user credentials when NATIVE authentication is enabled.
- SYSVIEWS system table
  The SYSVIEWS table describes the view definitions within the current database.