SQL/MX 3.2.1 Reference Manual (H06.26+, J06.15+)

SQL/MX Statements
HP NonStop SQL/MX Release 3.2.1 Reference Manual—691117-005
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Considerations for CREATE TRIGGER
insert-statement
is an insert statement to be performed when the AFTER trigger is activated.
signal-statement
is a statement to be sent to the SIGNAL statement.
set-new-statement
is an assignment statement that can be used as a BEFORE trigger action to
assign values to transition variables representing columns in the subject table
modified by the triggering action.
quoted-sqlstate
is the five-digit SQLSTATE to be passed to SIGNAL. Use the GET DIAGNOSTICS
command to retrieve quoted-string-expr (as message-text) and
quoted-sqlstate.
quoted-string-expr
is a string expression.
Considerations for CREATE TRIGGER
Triggers support up to 16 levels of recursion. Triggers have their own namespace.
SHOWDDL for a table displays the DDL CREATE text for all triggers defined on that
table. The LIKE option of CREATE TABLE ignores triggers.
Triggers and Utilities
•
The DUP utility does not duplicate triggers.
•
By default, using the IMPORT utility to import data to a table causes trigger actions
to be performed. If trigger actions are not required, use the -d option with the
IMPORT utility, which allows triggers to be disabled for the duration of the
operation.
•
Most of MODIFY’s partition management operations ignore triggers. However, the
REUSE form of MODIFY might return errors on a table with DELETE triggers.
•
Use PURGEDATA to purge the data of a table that is referenced by a trigger or that
is the subject of a trigger. PURGEDATA supports an option that indicates whether
DELETE triggers on the table are ignored. If they are not ignored and a DELETE
trigger exists, PURGEDATA fails.
•
BACKUP/RESTORE operations on tables ignore triggers.
•
The mxexportddl utility handles triggers correctly.
•
VERIFY operations ignore triggers.