Triggers, functions, views, stored procedures

Trigger : is a special storage process, it is a code block mysql performed automatically insert, update, delete time.

 the Create  the Trigger trigger_name 

　　 the After / the before INSERT  / Update / the Delete  ON table name 

　　 for the each Row 

　　 the begin 

　　 SQL statement :( statement triggered a multi-sentence) 

　　 End

Function : mysql provides many built-in functions, can also customize function (implemented logic programmer need sql)

Create a custom function syntax

　　 Creation: the CREATE  FUNCTION function name (parameter list) 　

　　　     RETURNS return value type of the function body 

 　　modification: the ALTER  FUNCTION function name [ Characteristic ... ] 

　　 deleted: DROP  FUNCTION  [ IF EXISTS ] name of the function 

　　 call: the SELECT function name (parameter list)

View : A view is a virtual table is formed by the query result, the projection is a calculation table obtained by some

create view view_name as select 语句

Stored procedures : a piece of code to encapsulate, when you want to execute this piece of code, can be achieved (after the first compilation called again need to compile again, a high efficiency ratio sql statement execution) by calling the stored procedure

 the Create  Procedure stored procedure name (parameter, parameter, ...) 

　　 the begin 

　　 // Code 

　　 end

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