Triggers are useful if you need to be sure that certain events always happen when data is inserted, updated or deleted. This is the case when you have to deal with complex default values of columns, or modify the data of other tables.
Is it good practice to use triggers?
Using remote queries in triggers is a bad practice. Distributed queries have detrimental effects on performance and you should avoid this practice if possible. In the case you have to implement referential integrity between databases residing on different servers try to keep the usage of remote queries to a minimum.
When would you use a trigger SQL?
Because a trigger resides in the database and anyone who has the required privilege can use it, a trigger lets you write a set of SQL statements that multiple applications can use. It lets you avoid redundant code when multiple programs need to perform the same database operation.
What are the benefits of using triggers?
Some of the prominent advantages of triggers are as follows:
- Helps us to automate the data alterations.
- Allows us to reuse the queries once written.
- Provides a method to check the data integrity of the database.
- Helps us to detect errors on the database level.
- Allows easy auditing of data.
Should I use mysql triggers?
Triggers are a natural choice for auditing database activity where the auditing records do not link back to the table(s) in question via foreign key and auditing activities do not have to be transmitted back to any intermediate application or process. The trigger_time must be either BEFORE or AFTER.
Why you shouldn’t use triggers?
They are also the best place for auditing unless you don’t want to capture all changes to the database (which is the problem of auditing from the application). Triggers can cause performance issues if not written carefully and not enough developers are knowledgeable enough to write them well.
Are triggers bad SQL?
Triggers are generally over-used in SQL Server. They are only rarely necessary, can cause performance issues, and are tricky to maintain If you use them, it is best to keep them simple, and have only one operation per trigger.
What are the disadvantages of trigger?
Disadvantages(Problems) of Triggers
- It is easy to view table relationships , constraints, indexes, stored procedure in database but triggers are difficult to view.
- Triggers execute invisible to client-application application.
Does trigger impact performance?
So the answer is No, not without a heavy cost to implement the logic in application level . As I know, triggers will affect performance in insert, update and delete operations. but doesn’t affect read performance.
Is it safe or risky to use triggers?
The general consensus here is that triggers are indeed harmful. Because they change the well known semantics of an INSERT, UPDATE or DELETE statement.
Do triggers slow down database?
A trigger fires inside the transaction that modifies the data in the table. … The triggers of this type will not slow down operations, however, will ensure data coupling and integrity.
Is trigger a database object?
A trigger is a named database object that is associated with a table, and that activates when a particular event occurs for the table. Some uses for triggers are to perform checks of values to be inserted into a table or to perform calculations on values involved in an update.
How many tables can a trigger associate to in MySQL?
MySQL triggers fire depending on the activation time and the event for a total of six unique trigger combinations.
Why do we need triggers in database?
Triggers help the database designer ensure certain actions, such as maintaining an audit file, are completed regardless of which program or user makes changes to the data. The programs are called triggers since an event, such as adding a record to a table, fires their execution.