Oracle triggers if inserting updating

The CREATE TRIGGER statement has a lot of permutations, but the vast majority of the questions I'm asked relate to basic DML triggers.Of those, the majority are related to people misunderstanding the order of the timing points and how they are affected by bulk-bind operations and exceptions.For example, when a new record (representing a new worker) is added to the employees table, new records should also be created in the tables of the taxes, vacations and salaries.

In addition to triggers that fire when data is modified, Oracle 10g supports triggers that fire when schema level objects (that is, tables) are modified and when user logon or logoff events occur.PUT_LINE('Record successfully inserted into emp_backup table'); END; Second Problem: We want o update a record in the ’emp_backup’ table if a corresponding record is updated in the ’emp’ table.As we’ve already created both the tables in above example, we will directly write a trigger for ‘AFTER UPDATE’.Thanks Here's an example (based on Scott's schema) of how you might do that.First, create a LOG table (which will contain changes made on the "original" DEPT table).These trigger types are referred to as "Schema-level triggers". Performing conditional actions in triggers (or testing data following modification) is done through accessing the temporary Inserted and Deleted tables. The following functionality in SQL:2003 was previously not implemented in Postgre SQL: Firebird supports multiple row-level, BEFORE or AFTER, INSERT, UPDATE, DELETE (or any combination thereof) triggers per table, where they are always "in addition to" the default table changes, and the order of the triggers relative to each other can be specified where it would otherwise be ambiguous (POSITION clause.) Triggers may also exist on views, where they are always "instead of" triggers, replacing the default updatable view logic.

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