Using SET DATABASE

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The SET DATABASE statement is used to:

  • Declare a database handle for each database used in a SQL program.
  • Associate a database handle with an actual database name. Typically, a database handle is a mnemonic abbreviation of the actual database name.

SET DATABASE instantiates a host variable for the database handle without requiring an explicit host variable declaration. The database handle contains a pointer used to reference the database in subsequent SQL statements. To include a SET DATABASE statement in a program, use the following syntax:

EXEC SQL
SET DATABASE handle = 'dbname';

A separate statement should be used for each database. For example, the following statements declare a handle, DB1, for the employee.ib database, and another handle, DB2, for employee2.ib:

EXEC SQL
SET DATABASE DB1 = 'employee.ib';
EXEC SQL
SET DATABASE DB2 = 'employee2.ib';

Once a database handle is created and associated with a database, the handle can be used in subsequent SQL database and transaction statements that require it, such as CONNECT.

Note: SET DATABASE also supports user name and password options. For a complete discussion of SET DATABASE options, see Working with Databases.