规范化的SQL数据修改语句总结_MySQL
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1 增加字段
IF NOT EXISTS (SELECT * FROM SYSCOLUMNS WHERE ID=OBJECT_ID('QueryDataSource') and name = 'IsCrossTable')
BEGIN
ALTER TABLE QueryDataSource ADD IsCrossTable bit default(0) --插入字段
END
2 存储过程
if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[PLSystem_Insert]') and OBJECTPROPERTY(id, N'IsProcedure') = 1)
drop procedure [dbo].[PLSystem_Insert]
go
CREATE PROCEDURE dbo.PLSystem_Insert
(
@PLSystemID smallint,
@PLSystemName varchar(20),
@PLSystemFlag char(2)
)
AS
INSERT INTO dbo.PLSystem
(
PLSystemID,
PLSystemName,
PLSystemFlag
)
VALUES
(
@PLSystemID,
@PLSystemName,
@PLSystemFlag
)
go
if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[PLSystem_Delete]') and OBJECTPROPERTY(id, N'IsProcedure') = 1)
drop procedure [dbo].[PLSystem_Delete]
go
CREATE PROCEDURE dbo.PLSystem_Delete
(
@PLSystemID smallint
)
AS
DELETE FROM dbo.PLSystem
WHERE
PLSystemID = @PLSystemID
go
if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[PLSystem_Update]') and OBJECTPROPERTY(id, N'IsProcedure') = 1)
drop procedure [dbo].[PLSystem_Update]
go
CREATE PROCEDURE dbo.PLSystem_Update
(
@PLSystemID smallint,
@PLSystemName varchar(20),
@PLSystemFlag char(2)
)
AS
UPDATE dbo.PLSystem SET
PLSystemName = @PLSystemName,
PLSystemFlag = @PLSystemFlag
WHERE
PLSystemID = @PLSystemID
go
3 创建表
IF EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[PLSystem]') AND type in (N'U'))
DROP TABLE [dbo].[PLSystem]
GO
IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[PLSystem]') AND type in (N'U'))
BEGIN
CREATE TABLE [dbo].[PLSystem](
[PLSystemID] [tinyint] NOT NULL,
[PLSystemName] [varchar](20) NULL,
[PLSystemFlag] [char](2) NULL,
CONSTRAINT [XPKPLSystem] PRIMARY KEY CLUSTERED
(
[PLSystemID] ASC
)
) ON [PRIMARY]
END
GO
4 游标
Begin
declare @PluserID varchar(8)
declare pluserCurse Cursor for select PLUserID from PLUser where PCancelJudge=0
open pluserCurse --打开游标
fetch next from pluserCurse into @PluserID
while @@FETCH_STATUS=0
begin
print (@PluserID)
insert into PLUserActorDepart(DepartID,PLActorSystemID,PLUserID)
select DepartmentID,PLSystemID,PLUserID from MSUserRight where MSUserRight.DepartmentID not in
(
select DepartmentID from PLDepartment where PLDepartment.DParent=(select DepartmentID from PLUser where PLUserID=@PluserID )
OR PLDepartment.DepartmentID=(select DepartmentID from PLUser where PLUserID =@PluserID)
) AND MSUserRight.PLUserID=@PluserID
fetch next from pluserCurse into @PluserID
end
close pluserCurse
deallocate pluserCurse
end
5 用while实现for循环
Create Proc InsertSQL
AS
Begin
DECLARE @Count int
set @Count=0;
While(@CountBegin
Print(@Count);
Insert into Student values('YOUNG','M',100,'FUJIANXIAMENT');
set @Count=@Count+1;
END
END
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