Why we need triggers?

Question

Why we need triggers? How many types they are? Any Example?

Code Alone · Accepted Answer

"A Trigger is a Database object just like a stored procedure or we can say it is a special kind of Stored Procedure which fires when an event occurs in a database.".  It is a database object that is bound to a table and is executed automatically. We cannot explicitly call any trigger. Triggers provide data integrity and used to access and check data before and after modification using DDL or DML query.   To know more about triggers , I prefer below articles :  https://www.c-sharpcorner.com/UploadFile/a53f1a/triggers-in-sql-server/ https://www.c-sharpcorner.com/UploadFile/37db1d/creating-and-managing-triggers-in-sql-server-20052008/     **This is an interview question. So try to put these type of questions in that section..

Jignesh Kumar · Answer

Please find below link where realtime example is there   Trgger is mainly used to perform action when you performa operation in table. once you insert, update and delete from table that time trigger automatically executes. please have a look at below link which will clear.    https://www.dotnettricks.com/learn/sqlserver/after-trigger-instead-of-trigger-example

Shashangka Shekhar · Answer

Please follow the link: https://www.c-sharpcorner.com/UploadFile/63f5c2/triggers-in-sql-server/ http://www.mysqltutorial.org/sql-triggers.aspx

Navjot Angra · Answer

Hi, Suppose u want to restrict some operation in your database,it means that u want without your permisson no one can insert ,update ,delete or other operations . So Can Can doit with triggers. In Simple words ,it automatically called or invoked when undesire thing will happen

Shweta68 · Answer

Thanks to all. All answers helped me a lot.

Karthikeyan K · Answer

Please find the below link you will get an idea clearly.   https://docs.oracle.com/cd/B13789_01/appdev.101/b10795/adfns_tr.htm