OceanBase Database provides triggers in Oracle tenants. A trigger is similar to a procedure or a function. It is a PL block that contains a declaration section, an execution section, and an exception-handling section. A trigger is executed when a specific event occurs. You can specify to execute a trigger before or after an event. You can also specify to execute a trigger by a specific event or any event that affects a specific row of data.
A trigger is an independent object that is implicitly executed when a specific event occurs. A trigger does not accept parameters. The triggering event can be an INSERT, UPDATE, or DELETE operation. Notice
OceanBase Database V2.2.7x and earlier versions only support row-level triggers on tables.
A simple triggered is executed at one of four following points:
A statement-level BEFORE trigger is executed before the triggering event executes.
A statement-level AFTER trigger is executed after the triggering event executes.
A row-level BEFORE trigger is executed before a specific row is affected.
A row-level AFTER trigger is executed after a specific row is affected.
A DML statement may trigger many simple triggers, which are executed in the following order: statement-level BEFORE trigger -> row-level BEFORE trigger -> row-level AFTER trigger -> statement-level AFTER trigger. The execution order of the same type of trigger is uncertain. Currently, you cannot specify an execution order for triggers.