Circumstances When a Select Trigger is Not Activated

In Dynamic Server, a SELECT statement on the triggering table does not activate a Select trigger in certain circumstances:

• If a subquery or UDR that contains the triggering SELECT statement appears in any clause of a SELECT statement other than the Projection clause, the Select trigger is not activated.

  For example, if the subquery or UDR appears in the WHERE clause or HAVING clause of a SELECT statement, the SELECT statement within the subquery or UDR does not activate the Select trigger.

• If the trigger action of a Select trigger calls a UDR that includes a triggering SELECT statement, the Select trigger on the SELECT in the UDR is not activated. Cascading Select triggers are not supported.
• If a SELECT statement contains a built-in aggregate or user-defined aggregate in its Projection clause, the Select trigger is not activated. For example, the following SELECT statement does not activate a Select trigger defined on col1 of tab1:

  SELECT MIN(col1) FROM tab1

• A SELECT statement that includes the UNION or UNION ALL operator does not activate a Select trigger.
• The SELECT clause of INSERT does not activate a Select trigger.
• If the Projection clause of a SELECT includes the DISTINCT or UNIQUE keywords, the SELECT statement does not activate a Select trigger.
• Select triggers are not supported on scroll cursors.
• If a SELECT statement refers to a remote triggering table, the Select trigger is not activated on the remote database server.
• Columns in the ORDER BY list of a query activate no Select triggers (nor any other triggers) unless also listed in the Projection clause.