You can submit SQL statements directly to the data source by using a special way called delivery (pass-through). You can submit SQL statements in the SQL language used by the data source. Use a pass-through (pass-through) session when you want to perform an operation that DB2 (R) Sql/api cannot do. For example, use a pass-through (pass-through) session to create a procedure, create an index, or execute a query in the native language of a data source.
Currently, data sources that support delivery (pass-through) support the use of delivery using SQL. In the future, a data source might be able to support the use of a data source language other than SQL (pass-through).
Similarly, you can use a pass-through (pass-through) session to perform operations that are not supported by SQL (for example, some administrative tasks). However, you cannot use a pass-through (pass-through) session to perform all administrative tasks. For example, you can create or delete tables on a data source table, but you cannot start or stop a remote database.
You can use both static SQL and dynamic SQL in a pass-through (pass-through) session.
The federation server provides the following SQL statements to manage delivery (pass-through) sessions: SET PassThru Open Delivery (pass-through) sessions. When you issue another SET PassThru statement to start a new delivery (pass-through) session, the current delivery session is terminated. SET PassThru RESET Terminates the current delivery (pass-through) session. Grant (server privileges) grants the user, group, and authorization identity list or public permission to start a delivery (pass-through) session with a specific data source. REVOKE (server privileges) cancels the right to initiate a delivery (pass-through) session.
The following restrictions apply to delivery (pass-through) sessions: You must use the SQL Language command for the data source, not the DB2 SQL language. Therefore, you do not query the nickname, but query the data source object directly. When you perform an UPDATE or DELETE operation in a pass-through (pass-through) session, you cannot use the WHERE current of CURSOR condition. 2 LOB is not supported in the delivery (pass-through) session.