Updating pl sql
4)If you ROLLBACK the transaction before committing to the database, the data inserted to the table is also rolled back.There are two types of triggers based on the which level it is triggered.SQL is a powerful language for both querying and updating data in relational databases.Oracle created PL/SQL that extends some limitations of SQL to provide a more comprehensive solution for building mission-critical applications running on Oracle database.For Example: The price of a product changes constantly.
where (column1,column2) in ( If your table t1 and it's backup t2 have many columns, here's a compact way to do it.
For Example: Let's create a table 'product_check' which we can use to store messages when triggers are fired.
Let's create a BEFORE and AFTER statement and row level triggers for the product table.
This events will alternates between BEFORE and AFTER row level triggers.
4) Finally the AFTER statement level trigger fires.