Ix. The concept of MySQL triggers

1. 1The so-called Trigger refers to an action that sets up a table (Insert,Update,Deleteat the same time, an operation that is triggered at the same time; generally used, for example, to delete the main column of the article, then you can use the trigger to delete all the articles under this article column2. Create a trigger delimiter $$Create TriggerIns_1 beforeInsert  onTt1 forEach rowBEGIN    Insert  intoTt2Values(now ()); END;    $$ above trigger, probably means: when TT1 has to insert the operation, that is to do tt2 insert operation, and then perform TT1 insert operation!! PS:: BeforeInsertInsert before executing afterInsertexecute before after insertingUpdateupdate before executing afterUpdateExecute after Update3.Drop TriggerIns_1 to delete a trigger named Ins_14. Show triggers view all triggers