Please explain compound trigger in Oracle?

The compound trigger was in introduced in Oracle 11g. This single trigger on a table enables the user to specify the actions for each of the four timing points:

• Before the firing statement
• Before each row that the firing statement affects
• After each row that the firing statement changes
• After the firing statement

In other words, Compound trigger merges all the four triggering events into the single piece of code, and as a result, the performance of the database server is improved during the bulk operations. The Compound trigger is only for the DML triggers.