1 is a database trigger qi https://www.cnblogs.com/phpper/p/7587031.html
① By default, delimiter ";" to submit queries to MySQL. During storage at the end of each SQL statement has a ";" if this time, every ";" submitted to MySQL, then, of course, a problem. Then change the MySQL delimiter.
②show triggers View all flip-flops
③drop trigger trigger_name; remove a trigger.
2, the database stored procedures https://www.cnblogs.com/mark-chan/p/5384139.html .
① are used to access mssql server, probably when using N records before mysql query, accustomed to the use of select top n the form of statements explain here, mysql without this grammar, mysql to carry out their functions with the limit, but also functions more powerful
eg: select * from student limit 0,15 (Select the previous 15)
② The results will be stored in the select statement to the variable https://bbs.csdn.net/topics/310205980
③ added before MySQL stored procedure variable @ symbol represents the session variable scoping is the current login account variables DECLARE declared valid only within the stored procedure.
④ if-then-end statement format:
BEGIN
if (条件)
then
......
end if;
END
declare variables can not be declared inside an if statement
2, database event https://www.jb51.net/article/83430.htm
① timed events do one of the reasons for the success is not possible because the trigger associated with execution error. If you timed event calls a function, this time we must try to run it.