Mssql trigger on update insert

Because SQL Server does not support user-defined triggers on system tables, we recommend that you do not create user-defined triggers on system tables.

Triggers work in transactions implied or otherwise and while they're open, they lock resources. The longer a trigger runs, the higher the probability that another process is then blocked. So, write triggers to lessen their duration whenever possible. One way to achieve shorter duration is to release a trigger when a DML statement changes zero rows. The following T-SQL code snippet shows how to release the trigger for a command that doesn't change any rows. This code should be present at the beginning of each DML trigger:.

DDL triggers, like standard triggers, launch stored procedures in response to an event. Instead, they primarily run in response to data definition language DDL statements. Test your DDL triggers to determine their responses to system stored procedure execution.

DDL triggers don't fire in response to events that affect local or global temporary tables and stored procedures. Use the catalog views instead. This folder is located under the Server Objects folder. This folder is located under the Programmability folder of the corresponding database. This event happens when a user session is established with an instance of SQL Server.

Logon triggers fire after the authentication phase of logging in finishes, but before the user session is established. So, all messages originating inside the trigger that would typically reach the user, such as error messages and messages from the PRINT statement, are diverted to the SQL Server error log. For more information, see Logon Triggers. Distributed transactions aren't supported in a logon trigger.

Error returns when a logon trigger that contains a distributed transaction fire. A logon trigger can effectively prevent successful connections to the Database Engine for all users, including members of the sysadmin fixed server role.

When a logon trigger is preventing connections, members of the sysadmin fixed server role can connect by using the dedicated administrator connection, or by starting the Database Engine in minimal configuration mode -f. The ability to return results from triggers will be removed in a future version of SQL Server. Triggers that return result sets may cause unexpected behavior in applications that aren't designed to work with them.

Avoid returning result sets from triggers in new development work, and plan to modify applications that currently do. To prevent triggers from returning result sets, set the disallow results from triggers option to 1.

Logon triggers always disallow the return of results sets and this behavior isn't configurable. If a logon trigger generates a result set, the trigger fails to launch and the login attempt that fired the trigger is denied.

With indirect recursion, an application updates table T1. This fires trigger TR1, updating table T2. Trigger T2 then fires and updates table T1. In direct recursion, the application updates table T1. This fires trigger TR1, updating table T1.

Because table T1 was updated, trigger TR1 fires again, and so on. The following example uses both indirect and direct trigger recursion Assume that two update triggers, TR1 and TR2, are defined on table T1. Trigger TR1 updates table T1 recursively. The inserted and deleted tables for a specific trigger contain rows that correspond only to the UPDATE statement that invoked the trigger.

There's no defined order in which multiple triggers defined for a specific event are run. Each trigger should be self-contained. You can nest triggers to a maximum of 32 levels. If a trigger changes a table on which there's another trigger, the second trigger activates and can then call a third trigger, and so on.

If any trigger in the chain sets off an infinite loop, the nesting level is exceeded and the trigger is canceled.

When a Transact-SQL trigger launches managed code by referencing a CLR routine, type, or aggregate, this reference counts as one level against the level nesting limit. I'm making a simple table with names, emails etc, but I also have a ModifiedDate. My idea is to use a trigger after both insert and update, and insert the current date. Thus if anyone does anything except delete to that column, the date should reflect that. Now I have a couple of values that can't be null, and what this seems to do is try and create a new row.

I would like it to insert the date into the row that is currently being acted upon, I have no idea how though. Also what if I add 5 rows at once? You need to join the inserted virtual table in the trigger to limit the rows that get updated to those actually changed.

Try this:. Like ZoharPeled correctly pointed out in a comment below there's really not much point in having the trigger update the date on insert - it would be better to use getdate as the default value on the column or even as another column InsertedDate if you want to track when records were initially created and have the trigger only modify the ModifiedDate column after updates.

See the documentation for more information on the inserted and deleted tables. If you don't have keys on the insert data and you are not in command of the sql to add a default on the modifieddate column, you can get the insert trigger where the modifieddate column is null:. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Trigger on insert and update that adds modification date Ask Question.

Asked 6 years, 10 months ago. Instead of Triggers. These triggers are executed instead of any of the Insert, Update or Delete operations. Insert Trigger. Below is an example of an After Insert Trigger. Whenever a row is inserted in the Customers Table, the following trigger will be executed. The following Trigger is fetching the CustomerId of the inserted record and the fetched value is inserted in the CustomerLogs table.

ON [dbo]. Update Trigger. Below is an example of an After Update Trigger. Whenever a row is updated in the Customers Table, the following trigger will be executed. The following Trigger is fetching the CustomerId of the updated record. Finally based on which column of the record has been updated a record containing the CustomerId and the appropriate action is inserted in the CustomerLogs table.

Delete Trigger. Below is an example of an After Delete Trigger. Whenever a row is delete in the Customers Table, the following trigger will be executed. The following Trigger is fetching the CustomerId of the deleted record and the fetched value is inserted in the CustomerLogs table. The following screenshot displays the Log table after the above Triggers were executed. Instead Of Triggers. Below is an example of an Instead Of Delete Trigger.

Whenever anyone tries to delete a row from the Customers table the following trigger is executed.