超难的数据库查询删除操作，跪求高手解答

declare @id int, @tabname varchar(256),@colname sysname;

declare @sql varchar(1000);



declare tab_c cursor local for

 select id from sysobjects where type='U';

 

open tab_c;



fetch next from tab_c into @id;

while @@fetch_status=0

begin

 set @tabname=quotename(object_schema_name(@id))+'.'+quotename(object_name(@id));



 declare col_c cursor local for

  select name from syscolumns where id=@id and xtype in (175,167,231,239) and length>=4;

 open col_c;

 fetch next from col_c into @colname;

 while @@fetch_status=0

 begin

  set @sql='delete from '+@tabname+' where '+quotename(@colname)+' like ''%K216%''';

  print @sql;

--  exec(@sql);

  fetch next from col_c into @colname;

 end

 close col_c;

 deallocate col_c;

 

 fetch next from tab_c into @id;

end



close tab_c;

'参考：获取数据库test中含有null值的数据表及字段名'

use test

go

if object_id('test.dbo.tb1') is not null drop table tb1

-- 创建数据表

create table tb1

(

a1 char(2),

b1 char(2),

c1 int

)

go

--插入测试数据

insert into tb1 select 'A','B',2

union all select 'A','C',3

union all select 'A','D',null

union all select 'B',null,3

union all select 'B','E',8

union all select 'E','F',null

union all select 'E','G',3

go

if object_id('test.dbo.tb2') is not null drop table tb2

-- 创建数据表

create table tb2

(

a2 char(2),

b2 char(2),

c2 int

)

go

--插入测试数据

insert into tb2 select 'A','B',2

union all select 'A','C',null

union all select 'A','D',5

union all select 'B','C',3

union all select null,'E',null

union all select 'E','F',2

union all select 'E','G',3

go

if object_id('test.dbo.tb3') is not null drop table tb3

-- 创建数据表

create table tb3

(

a3 char(2),

b3 char(2),

c3 int

)

go

--插入测试数据

insert into tb3 select 'A','B',2

union all select 'A','C',3

union all select 'A','D',5

union all select 'B','C',3

union all select 'B','E',8

union all select 'E','F',2

union all select 'E','G',3

go

-->代码实现

if object_id('test.dbo.result') is not null drop table result

create table result(tbname varchar(30),tbcolumn varchar(30))--存储结果

--获取数据库 test 中的所有表名：

if object_id('test.dbo.nametemptable') is not null drop table nametemptable

create table nametemptable(tbname varchar(30))--存储表名

insert into nametemptable

select name from test..sysobjects where type='u' and name not in('columntemptable','nametemptable','result')

--选出 null 字段：

declare @tbname varchar(30),

@colname varchar(30),

@sqlstr varchar(max),

@tb_i int,

@tb_total int,

@col_i int,

@col_total int

select @tb_total=count(*),@tb_i=1 from nametemptable

while(@tb_i<=@tb_total)

begin

	if object_id('test.dbo.columntemptable') is not null drop table columntemptable

	create table columntemptable(tbcolumn varchar(30))

	select top 1 @tbname=tbname from nametemptable

	where tbname not in (select top (@tb_i-1) tbname from nametemptable)

	exec('insert into columntemptable

	Select Name FROM SysColumns Where id=Object_Id('''+@tbname+''')')

	select @col_total=count(*),@col_i=1 from columntemptable

	while(@col_i<=@col_total)

	begin

		select top 1 @colname=tbcolumn from columntemptable

		where tbcolumn not in (select top (@col_i-1) tbcolumn from columntemptable)

		exec('if exists(select * from '+@tbname+' where '+@colname+' is null)

		insert into result select '''+@tbname+''','''+@colname+'''')

		set @col_i=@col_i+1

	end

	set @tb_i=@tb_i+1

	drop table columntemptable

end

--测试：

select * from result

/*测试结果：



tbname tbcolumn

-----------------------

tb1	b1

tb1	c1

tb2	a2

tb2	c2



(4 行受影响)

*/

drop table nametemptable,result

















################################## 方法二 #################################



IF OBJECT_ID('TEMPDB..#T') IS NOT NULL

    DROP TABLE #T

GO

CREATE TABLE #T(TBNAME NVARCHAR(20),COLNAME NVARCHAR(20))

SET NOCOUNT ON

DECLARE @S NVARCHAR(4000)

DECLARE C CURSOR FOR

    SELECT 'IF EXISTS(SELECT 1 FROM ['+B.NAME+'] WHERE ['+A.NAME+'] IS NULL)

                INSERT #T SELECT '''+B.NAME+''','''+A.NAME+''''

    FROM SYSCOLUMNS A JOIN SYSOBJECTS B ON A.ID=B.ID AND B.TYPE='U'

OPEN C

FETCH C INTO @S

WHILE @@FETCH_STATUS=0

BEGIN

    EXEC(@S)

    FETCH C INTO @S

END

CLOSE C

DEALLOCATE C

SET NOCOUNT OFF

SELECT * FROM #T

/*

TBNAME               COLNAME

-------------------- --------------------

tb1                  b1

tb1                  c1

tb2                  a2

tb2                  c2



(4 行受影响)

*/