SQL语句和存储过程 查询语句的流程控制

SQL语句和存储过程 查询语句的流程控制 - 应用软件 - 电脑教程网

SQL语句和存储过程 查询语句的流程控制

日期:2007-10-14   荐:
  drop table classname declare @TeacherID int declare @a char(50) declare @b char(50) declare @c char(50) declare @d char(50) declare @e char(50) set @TeacherID=1 select @a=DRClass1, @b=DRClass2, @c=DRClass3, @d=DRClass4, @e=DRClass5 from Teacher Where TeacherID = @TeacherID create table classname(classname char(50)) insert into classname (classname) values (@a) if (@b is not null) begin insert into classname (classname) values (@b) if (@c is not null) begin insert into classname (classname) values (@c) if (@d is not null) begin insert into classname (classname) values (@d) if (@e is not null) begin insert into classname (classname) values (@e) end end end end select * from classname 以上这些SQL语句能不能转成一个存储过程?我自己试了下 ALTER PROCEDURE Pr_GetClass @TeacherID int, @a char(50), @b char(50), @c char(50), @d char(50), @e char(50) as select @a=DRClass1, @b=DRClass2, @c=DRClass3, @d=DRClass4, @e=DRClass5 from Teacher Where TeacherID = @TeacherID DROP TABLE classname create table classname(classname char(50)) insert into classname (classname) values (@a) if (@b is not null) begin insert into classname (classname) values (@b) if (@c is not null) begin insert into classname (classname) values (@c) if (@d is not null) begin insert into classname (classname) values (@d) if (@e is not null) begin insert into classname (classname) values (@e) end end end end select * from classname 但是这样的话,这个存储过程就有6个变量,实际上应该只提供一个变量就可以了 主要的问题就是自己没搞清楚 @a,@b,@C,@d 等是临时变量,是放在as后面重新做一些申明的,而不是放在开头整个存储过程的变量定义。

  写好的存储过程如下create PROCEDURE Pr_GetClass @TeacherID intas Declare @a char(50), @b char(50), @c char(50), @d char(50), @e char(50) select @a=DRClass1, @b=DRClass2, @c=DRClass3, @d=DRClass4, @e=DRClass5 from Teacher Where TeacherID = @TeacherID DROP TABLE classname create table classname(classname char(50)) insert into classname (classname) values (@a) if (@b is not null) begin insert into classname (classname) values (@b) if (@c is not null) begin insert into classname (classname) values (@c) if (@d is not null) begin insert into classname (classname) values (@d) if (@e is not null) begin insert into classname (classname) values (@e) end end end end select * from classname go2 连表查询我有三个表KJ表KJIDTeacherID..........................................................Teacher表TeacherIDTeacherNameCollageID.........................................................Collage表CollageIDCollageName我想写一个SQL语句,查询所有的KJ,根据KJ的TeacherID查到TeacherName,同时根据TeacherID查到Teacher,Teacher的CollageID查到Collage,最后生成的数据集里KJ的属性里除了本身的KJName以外,还想加上TeacherName,CollageName。语句如下 SELECT T1.KJName, T2.TeacherName, T3.CollageName FROM KJ T1 LEFT JOIN Teacher T2 ON T2.TeacherID=T1.TeacherID LEFT JOIN Collage T3 ON T3.CollageID=T2.CollageID
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