表名和比较字段可以做参数的存储过程
创建存储过程
表名和比较字段可以做参数的存储过程
Create PROCEDURE sp_getTeacherInfo
@TblName nvarchar(30), -- 表名
@CmpStr nvarchar(30), -- 参与比较的值
@TblAtr nvarchar(30) -- 参与比较的字段
AS
DECLARE @sql varchar(4000)
SET @sql = 'select * from ' + @TblName + ' where ' + @TblAtr + '=' + @CmpStr
EXEC (@sql)
表 tbl_TeacherInfo
Exec sp_getTeacherInfo 'tbl_TeacherInfo','TeaNo', '07417502'
// 注意:像这样的调用是错误的
还原成查询语句
select * from tbl_TeacherInfo where TeaNo = 07417502
之所以没报错,是因为参数'07417502'被误认为了 整型,进行了整数的比较
Exec sp_getTeacherInfo 'tbl_TeacherInfo','Name','楚留香'
// 报错
还原成查询语句
select * from tbl_TeacherInfo where TeaNo = 楚留香
// 显然是错误的
正确的调用方法
Exec sp_getTeacherInfo 'tbl_TeacherInfo','Name',"'楚留香' "
还原成查询语句
select * from tbl_TeacherInfo where TeaNo = '楚留香'
常规存储过程的创建
Create PROCEDURE sp_AddRowToLogin
@TeaNo nvarchar(100), -- 比较字段
@TeaName nvarchar(100) -- 比较字段
AS
insert into tbl_UserLogin values(@TeaNo,@TeaName,@TeaNo,0)
除了指定列其他列都返回的存储过程
CREATE PROCEDURE sp_Alter
@TblName nvarchar(30) -- 表名
AS
declare @sql varchar(1000)
select @sql='select '
select @sql=@sql+name+',' from syscolumns where id=object_id(@TblName) and name not in ('ID','TeaNo')
select @sql=left(@sql,len(@sql)-1)
select @sql=@sql+' from ' + @TblName
exec (@sql)
// 除了ID和TeaNo两列不返回,其他都返回

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