MySQL Flip-flop explanation

Trigger (Trigger): The supervisor of a situation, and set out some kind of operation.

Trigger creation Syntax Four elements: 1, watch location (table) 2, monitor event (Insert/update/delete)

3, Trigger Time (After/before) 4, trigger event (Insert/update/delete)

Create Trigger Triggername

After/before (3) Insert/update/delete (2) on TableName (1)

For each row

Begin

SQL statements (4)

End

*1,2,3,4 corresponds to four elements

Let's start by creating two tables:

#test_datax

Create Table Test_datax (

user_id Int (12),

User_name varchar (225),

Latesttime Timestamp

);

#uptable

Create Table Uptable (

user_id Int (12),

User_name varchar (225),

Latesttime Timestamp

);

Delimiter $

Create Trigger TG1

After update on Test_datax

For each row

Begin

Insert into uptable (user_id,user_name,latesttime) values (old.user_id,new.user_name,new.latesttime);

end$

MySQL Flip-flop explanation