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mysql ????????????????????????(1)?????? mysql?????????????????????????????????????????????????????????????????? ????????????????????????: Create procedure ProcedureName(Params[in,out]) Begin ???????? Declare?? attr attrType; ??????????proce mysql ????????????????????????(1)?????? mysql??????????????????????????????????????????????????????????????????????????????????????????:Create procedure ProcedureName(Params[in,out])Begin???????? Declare?? attr attrType;??????????procedure content;End;??Example:1. ????????????????????????create procedure exampe1()begin?????????? declare l_student_count integer;?????????? select count(*) into l_student_count from student;???????????? ??select concat('there are totally ', l_student_count ,' students');end;??2.?????????????????????? drop procedure example1;??3.??????????????????????????????create procedure example2(stu_id int) begin?????? declare stu_name varchar(30);?????????? select name into stu_name from student where student_id = stu_id;???????? select stu_name;end;??4.????????????????????????create function example5() returns intbegin???????? declare student_count int;???????????? select count(*) into student_count from student;?????????? return student_count;end;??5.???????????????????????????create trigger example6 before update on t for each rowbegin???? If New.percent ???? ????set New.percent = 20;???? Else???? ????set New.percent = 100;???? End If;End;