how to batch edit triggers? - sql

Question

I have many triggers for which I'd like to build a list of table using a wildcard, then update the existing triggers on them by adding some column names to the trigger. The column names will be the same in each trigger, but I'm not clear how build the list of tables or how to loop through the list in a single alter trigger statement. I assume I'll have to use a cursor....

Answer 1

There is no magic wand to say "add this code to all the triggers" (or any other object type, for that matter).
For many object types, for batch editing you can quickly generate a script for multiple objects using Object Explorer Details and sorting and/or filtering within that view. For example, if you highlight "Stored Procedures" in Object Explorer, they're all listed in Object Explorer Details, and you can select multiple objects, right-click, and Script Stored Procedure as > CREATE To >
Since triggers are nested under tables, there isn't a handy way to do this (nor are triggers an entity type you can select when you right-click a database and choose Tasks > Generate Scripts). But you can pull the scripts from the metadata quite easily (you'll want Results to Text in Management Studio when running this):
SET NOCOUNT ON;
SELECT OBJECT_DEFINITION([object_id])
+ CHAR(13) + CHAR(10) + 'GO' + CHAR(13) + CHAR(10)
FROM sys.triggers
WHERE type = 'TR';
You can take the output, copy and paste it into the top pane, then once you have added your new code to each trigger, you'll have to do a little more work to do, e.g. search/replace 'CREATE TRIGGER' for 'ALTER TRIGGER'. You could do that as part of the query too, but it relies on the creator(s) having consistent coding conventions. Since some triggers might look like this...
create trigger
... you may have to massage some by hand.
You can also filter the query above if you are only interested in a certain set of tables. For example, to only alter triggers associated with tables that start with Sales you could say:
AND OBJECT_NAME(parent_id) LIKE N'Sales%';
Or only for tables in the Person schema:
AND OBJECT_SCHEMA_NAME(parent_id) = N'Person';
Anyway once you have made all necessary adjustments to the script, you can just run it. A lot easier than expanding every single table and generating a script for those triggers.

Answer 2

In addition to Aarons suggestion, which worked great on a bunch of complex triggers with inconsistent object naming convention, I then attempted to cook something up so I'd remember what I did in 3 months. Enjoy. Create or alter the SP then execute with no params.
CREATE PROCEDURE SP_ALTER_CONTOUR_TRIGS
--sp to bulk edit many triggers at once
--NO ERROR HANDLING!
AS
DECLARE
#sql VARCHAR(500),
#tableName VARCHAR(128),
#triggerName VARCHAR(128),
#tableSchema VARCHAR(128)
DECLARE triggerCursor CURSOR
FOR
SELECT
so_tr.name AS TriggerName,
so_tbl.name AS TableName,
t.TABLE_SCHEMA AS TableSchema
FROM
sysobjects so_tr
INNER JOIN sysobjects so_tbl ON so_tr.parent_obj = so_tbl.id
INNER JOIN INFORMATION_SCHEMA.TABLES t
ON
t.TABLE_NAME = so_tbl.name
WHERE
--here's where you want to build filters to make sure you're
--targeting the trigs you want edited
--BE CAREFUL!
--test the select statement first against sysobjects
--to see that it returns what you expect
so_tr.type = 'TR'
and so_tbl.name like '%contours'
and so_tr.name like'%location_id'
ORDER BY
so_tbl.name ASC,
so_tr.name ASC
OPEN triggerCursor
FETCH NEXT FROM triggerCursor
INTO #triggerName, #tableName, #tableSchema
WHILE ( ##FETCH_STATUS = 0 )
BEGIN
--insert alter statement below
--watch out for cr returns and open and close qoutes!
--seems to act finicky if you don't use schema-bound naming convention
SET #sql = '
ALTER TRIGGER ['+ #tableSchema +'].['
+ #triggerName + '] ON ['+ #tableSchema +'].['
+ #tableName + ']
INSTEAD OF INSERT
AS
BEGIN
SET NOCOUNT ON;
INSERT ['+ #tableSchema +'].['+ #tableName + ']
(OBJECTID, Contour, Type, Shape, RuleID, Override)
SELECT
a.OBJECTID, a.Contour, a.Type, a.Shape, a.RuleID, a.Override
FROM
(SELECT
OBJECTID, Contour, Type, Shape, RuleID, Override
FROM inserted)
AS a
END
'
PRINT 'Executing Statement - '+ #sql
EXECUTE ( #sql )
FETCH NEXT FROM triggerCursor
INTO #triggerName, #tableName, #tableSchema
END
CLOSE triggerCursor
DEALLOCATE triggerCursor