Disadvantages of Using SQL Triggers :
. Trigger can provide extended validation and it cannot be replaced with all the validations.
. Simple validations can be done at the application level itself .
. Triggers executes invisibly from client-application which connects to the database server.So it is difficult to figure out what happens at the database layer.
. Triggers runs on every update made to the table therefore it adds more load to the database and cause the system to run slow.