A DB2 Everyplace database is comprised of several system catalog tables and a number of user-defined tables. Each table is stored in two files, one for the data itself and the other for indexes. All indexes will be kept in the same index file. Unlike DB2 Universal Database, DB2 Everyplace databases do not have names and cannot be cataloged or uncataloged. That is, the database name is ignored. In DB2 Everyplace, a database is merely a number of files that can be copied or moved to another location. System catalog tables contain metadata on user-defined tables. For example, if you remove files for a user-defined table without deleting a corresponding entry in the catalog tables this action will cause an inconsistency. A DB2 Everyplace database must contain the following system catalog tables:
To access catalog tables in a query, you must use delimited identifiers. For example, the following query returns if there exists a table T:
SELECT 1 FROM "DB2eSYSTABLES" WHERE TNAME = 'T'
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