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.
Methods invoked from within managed code don't count against this limit. The default configuration supports nested triggers. Review your applications for nested triggers to determine if the applications follow your business rules when the nested triggers server configuration option is set to 0.
If not, make the appropriate modifications. This ability is called deferred name resolution. The following DML trigger prints a message to the client when anyone tries to add or change data in the Customer table in the AdventureWorks database. 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. Inside the Trigger, I have added a condition that if record has CustomerId value 2 then such a record must not be deleted and an error must be raised. Also a record is inserted in the CustomerLogs table. If the CustomerId value is not 2 then a delete query is executed which deletes the record permanently and a record is inserted in the CustomerLogs table. The following error message shown when record with CustomerId 2 is deleted.
The following screenshot displays the Log table after the Instead Of Trigger is executed. Related Articles. Add Comments. Thank you for the feedback. The comment is now awaiting moderation. You will be notified via email when the author replies to your comment.
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We will manage this case using trigger in SQL Server database table. Here is the scenario or the business case. The transactions of company sales to the customers are stored in sql database table called Sales. Each sale's total amount is stored in [Net Amount] field in sql table Sales.
If the total amount is between 10, and 50, then the customer priority should be set to 2. If a more sales amount is reached for that customer, the customer priority database field should be 1.
Note that if no sales transaction has been created yet, that customer will not have any priority priority sql field will be NULL. The problem is that while executing this trigger. Queries applied to the FeedItems table are mostly timing out even those queries who dont uses the second table. I looked around on the internet, and I couldn't find any way of making the trigger happen without claiming a lock. Therefore I choose to do the inserts via a stored procedure, which in turn performs the logic previously found in the trigger.
This allowed me to execute the content of the trigger in a transaction AFTER the actual data was inserted and the insertion lock was lifted. 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. Asked 11 years, 9 months ago. Active 1 year, 4 months ago. Viewed 6k times. I have a serious performance problem. I have a database with related to this problem , 2 tables.
What do you think, if i'm right, is there a easy way around this? Thanks in advance!
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