Contents
Why are SQL triggers bad?
Triggers are often slower than other means of maintaining data integrity, so if you can use a check constraint, use that instead of a trigger. It is easy to write bad triggers that do stupid things like try to send emails. Do you really want to be unable to change records in the db if the email server goes down?
Are triggers bad mysql?
In my experience they are evil, because they can result in surprising side effects, and are difficult to debug (especially when one trigger fires another). Often developers do not even think of looking if there is a trigger.
What are constraints and triggers?
Explain the difference between Triggers and Constraints?
| Trigger | Constraints |
|---|---|
| Trigger affects only those rows, which are added after it is enabled. | Constraints affects all the rows i.e. the once that existed before and the ones that were newly added. |
What is the difference between constraint and trigger?
Major Difference Between Constraints and Triggers: The Trigger affects only the rows which are added after the trigger is enabled. Responsible for high-level business logic to implement as it is capable enough to handle the complicated business rules. Support data integrity but triggers can be imposed on many tables.
Is there an alternative to triggers in SQL Server?
Another alternative, but only valid after 2008 R2 is “Change Tracking” Setting up change tracking. While you can query rows to filter ( look here) what was changed, this may or may not “resolve” the issues with triggers.
When do you Don’t need a trigger?
It depends on your design philosophy. When you only change data with stored procedures then you don’t need triggers. Otherwise you may need triggers to maintain data integrity. Triggers wisely designed they are acceptable in terms of performance. You are asking the wrong question.
Can a trigger be used instead of a check?
The INSTEAD OF trigger cannot be used with the updatable views that have WITH CHECK OPTION and in the tables with a referential relationship that specifies cascade actions on DELETE or UPDATE. After discussing the triggers theoretically, we will start showing what we discuss practically.
When do you need the after update trigger?
If you need the AFTER UPDATE trigger to stop the update operation after raising the error message, the ROLLBACK statement can be added to the trigger in order to rollback the update operation that fired that trigger, recalling that the trigger and the statement that fires the trigger will be executed in the same transaction.