I need to delete a trigger in SQL Server. Seems like it should be simple enough, but because there is a thing called a "delete trigger", a trigger that is invoked upon deletion, it seems impossible to find resources on how to actually delete an already existing trigger.
DROP TRIGGER:
Removes one or more triggers from the current database...
You can remove a trigger by dropping it or by dropping the trigger table. When a table is dropped, all associated triggers are also dropped. When a trigger is dropped, information about the trigger is removed from the sysobjects and syscomments system tables.
Use DROP TRIGGER and CREATE TRIGGER to rename a trigger. Use ALTER TRIGGER to change the definition of a trigger...
To drop a trigger, this works:
DROP TRIGGER [trigger_name];
If you want to check weather trigger exist before a drop, then use:
SELECT * FROM [sys].[triggers] WHERE [name] = 'MyTrigger'
For more check out http://www.tsql.info/triggers/drop-trigger.php and https://stackoverflow.com/a/636470/2218697
I can Drop a Trigger with the Following Query
DROP TRIGGER [Trigger_Name]
(OR)
DROP TRIGGER Trigger_Update
Hope this Must helpfull...
For SQL Server 2016 and above
DROP TRIGGER IF EXISTS [dbo].[trg]
https://learn.microsoft.com/en-us/sql/t-sql/statements/drop-trigger-transact-sql
DROP TRIGGER IF EXISTS [dbo].[trigger_name];
Related
I have written a trigger, but it doesn't work well.
How to make it work to fill the column automatically, without user intervention, when I create an activity?
I use SQL Server.
You need an after trigger and not an instead of trigger change your trigger to after trigger
CREATE TRIGGER TriggerName
AFTER INSERT
ON TableName
BEGIN
//Your Code
END;
With 'For Insert' trigger, are rows inserted to the table yet when it is triggered?
CREATE Trigger check_availability on Room
For Insert, Update
Thanks!
Yes.
CREATE TRIGGER
FOR | AFTER
AFTER specifies that the DML trigger is fired only when all operations specified in the triggering SQL statement have executed successfully. All referential cascade actions and constraint checks also must succeed before this trigger fires.
AFTER is the default when FOR is the only keyword specified.
AFTER triggers cannot be defined on views.
I need to alter a trigger in SQL Server. After I am doing, do I just execute the trigger similar to how I would do for a Stored Procedure?
ALTER TRIGGER
Yes, that is right, just use ALTER. If you right-click on your trigger in Object Explorer in SSMS and select Script Trigger as/ALTER To, you will see the ALTER statement created for your trigger.
ALTER TRIGGER triggerName
ON tableName
FOR INSERT -- or update & delete
AS
-- sql here
http://msdn.microsoft.com/en-us/library/ms176072.aspx
You don't "execute" a trigger. Triggers are "triggered" at certain points depending upon your definition of them.
For example an AFTER UPDATE trigger would run for all rows updated after you send an UPDATE command to the table on which the trigger is created.
I have two triggers on one of the tables in my database. One is for insert trigger and the other is an after update trigger. The insert trigger will update the table with values. My question is this; Is it possible that that the update trigger is firing at the same time that the insert is doing its job?
A FOR INSERT trigger will fire only on INSERT statements. A FOR UPDATE trigger will fire only on UPDATE statements. Of course, if your insert trigger executes any UPDATE statements then it will fire the update trigger, and vice versa.
Your UPDATE trigger won't fire for an INSERT statement (excepting the update-within-trigger case above), but of course you still have to design for concurrency, since it's possible for two different users to be running two different operations at the same time - one INSERT and one UPDATE.
If your insert trigger does an update to the table, the update trigger will be called. If a trigger triggers another trigger, it's called a "recursive trigger".
Recursive triggers can be disabled for an entire server:
sp_configure 'nested_triggers', 0
go
reconfigure
Or for one database:
alter database yourdb set recursive_triggers off
I am working with SQL Server 2005 and I have trigger on a table that will copy an deletions into another table. I cannot remove this trigger completely. My problem is that we have now developed an archiving strategy for this table. I need a way of "pausing" a trigger when the stored proc that does the archiving runs.
A little more detail would be useful on how the procedure is accessing the data, but assuming you are just getting the data, then deleting it from the table and wish to disable the trigger for this process, you can do the following
DISABLE TRIGGER trg ON tbl;
then
ENABLE TRIGGER trg ON tbl;
for the duration of the procedure.
This only works for SQL 2005+
An alternative method is to use Context_Info to disable it for a single session, while allowing other sessions to continue to fire the trigger.
Context_Info is a variable which belongs to the session. Its value can be changed using SET Context_Info.
The trigger will mostly look like this:
USE AdventureWorks;
GO
-- creating the table in AdventureWorks database
IF OBJECT_ID('dbo.Table1') IS NOT NULL
DROP TABLE dbo.Table1
GO
CREATE TABLE dbo.Table1(ID INT)
GO
-- Creating a trigger
CREATE TRIGGER TR_Test ON dbo.Table1 FOR INSERT,UPDATE,DELETE
AS
DECLARE #Cinfo VARBINARY(128)
SELECT #Cinfo = Context_Info()
IF #Cinfo = 0x55555
RETURN
PRINT 'Trigger Executed'
-- Actual code goes here
-- For simplicity, I did not include any code
GO
If you want to prevent the trigger from being executed you can do the following:
SET Context_Info 0x55555
INSERT dbo.Table1 VALUES(100)
Before issuing the INSERT statement, the context info is set to a value. In the trigger, we are first checking if the value of context info is the same as the value declared. If yes, the trigger will simply return without executing its code, otherwise the trigger will fire.
source: http://www.mssqltips.com/tip.asp?tip=1591
if DISABLE TRIGGER/ENABLE TRIGGER is not an option for some reason, you can create a table with a single row which will serve as a flag for the trigger.