sqlserver对字段的添加修改删除、以及字段的说明

--新增表字段
ALTER  procedure [dbo].[sp_Web_TableFiled_Insert]
(
@TableName varchar(100),
@FieldName varchar(100),
@FieldExplain varchar(200),
@DataType varchar(100),
@ConnectTableName varchar(100),
@FieldLength int,
@NewsID int output

)
as
begin transaction mytran
declare @errorSum int
if not exists (SELECT * FROM syscolumns    where id=object_id(@TableName)   AND name=@FieldName)
begin
insert tb_TableField
(
TableName,
FieldName,
FieldExplain,
DataType,
ConnectTableName,
FieldLength,
UserSetSign
)
values
(
@TableName,
@FieldName,
@FieldExplain,
@DataType,
@ConnectTableName,
@FieldLength,
'1'
)

declare @sql varchar(8000)

--判断类型
if(@DataType='decimal')
begin

set @sql = 'alter table ' + @TableName +' add ' + @FieldName +' ' + @DataType +'(' +Convert(varchar,@FieldLength)+',2'+')'

end
else if(@DataType='varchar')
begin
set @sql = 'alter table ' + @TableName +' add ' + @FieldName +' ' + @DataType +'(' +Convert(varchar,@FieldLength)+')'

end
else
begin

set @sql = 'alter table ' + @TableName +' add ' + @FieldName +' ' + @DataType

end
exec(@sql)
EXECUTE sp_addextendedproperty   N'MS_Description', @FieldExplain,   N'user',  N'dbo',  N'Table', @TableName, N'column' , @FieldName;
 set @errorSum=@errorSum+@@error
 set @NewsID=0;
end
else
begin
set @NewsID=1;
end

if(@errorSum>0)
begin
 rollback tran
end
else
begin
   commit tran mytran
end

--修改表字段
ALTER  procedure [dbo].[sp_API_TableFiled_Update]
(
@TableName varchar(100),
@FieldName varchar(100),
@FieldExplain varchar(200),
@DataType varchar(100),
@ConnectTableName varchar(100),
@FieldLength int,
@PaySystemField varchar (100),
@ID int,
@NewsID int output

)
as
begin transaction mytran
begin try
declare @fname varchar(100)
declare @filetype varchar(20)
declare @tsql varchar(1000)
---先取出表中以前的字段名称
select  @fname=FieldName,@filetype=DataType from  tb_TableField where ID=@ID
declare @pstid int
declare @sql varchar(8000)
--再根据字段名称取出tb_PaySystemToLocation中对应的ID
select  @pstid=ID from  tb_PaySystemToLocation where LocationField=@fname

if(@filetype!=@DataType)--如果字段类型修改了
 begin
 if(@DataType='decimal')
begin
set @tsql = 'alter table ' + @TableName +' add ' + @FieldName +' ' + @DataType +'(' +Convert(varchar,@FieldLength)+',2'+')'
end
else if(@DataType='varchar')
begin
set @tsql = 'alter table ' + @TableName +' add ' + @FieldName +' ' + @DataType +'(' +Convert(varchar,@FieldLength)+')'
end
else
begin

set @tsql = 'alter table ' + @TableName +' add ' + @FieldName +' ' + @DataType
 
end
declare @delsql varchar(1000)
 set @delsql='ALTER TABLE ' +@tablename+ ' DROP COLUMN '+ @fname
exec(@delsql)--先删除旧字段 再添加新字段
exec(@tsql)
EXECUTE sp_addextendedproperty   N'MS_Description', @FieldExplain,   N'user',  N'dbo',  N'Table', @TableName, N'column' , @FieldName;
  end
  if(@fname!=@FieldName) begin
 set @sql = 'sp_rename '+CHAR(39)+@TableName+'.['+@fname+']'+CHAR(39)+',' +char(39)+@FieldName+char(39)+',' +  char(39)+'COLUMN' +CHAR(39)
exec(@sql)
end
update tb_TableField

set TableName=@TableName,
 FieldName=@FieldName,
 FieldExplain=@FieldExplain,
 DataType=@DataType,
 ConnectTableName=@ConnectTableName,
 FieldLength=@FieldLength
where ID=@ID
--修改字段说明
EXECUTE sp_updateextendedproperty   N'MS_Description', @FieldExplain,   N'user',  N'dbo',  N'Table', @TableName, N'column' , @FieldName;
update tb_PaySystemToLocation

set PaySystemField=@PaySystemField,LocationField=@FieldName,TableName=@TableName
where ID=@pstid
set @NewsID=0
commit tran mytran
end try
begin catch
insert into tb_error (Message)values(ERROR_MESSAGE())
set @NewsID=1
if(@@TRANCOUNT >0)
rollback transaction mytran
end catch

-删除表字段
ALTER  procedure [dbo].[sp_Web_TableFiled_Delete]
(
@ID int,
@NewsID int output
)
as
begin transaction mytran
declare @fname varchar(100)
declare @tablename varchar(100)
declare @pstid int
declare @sql varchar(8000)
declare @errorSum int
--取出字段名,表名
select  @fname=FieldName,@tablename=TableName from  tb_TableField where ID=@ID

--取出tb_PaySystemToLocation的ID
select  @pstid=ID from  tb_PaySystemToLocation where LocationField=@fname
delete from  tb_TableField where ID=@ID
set @sql='ALTER TABLE ' +@tablename+ ' DROP COLUMN '+ @fname
exec(@sql)
set @errorSum=@errorSum+@@error
set @NewsID=0;
if(@errorSum>0)
begin
 rollback tran
end
else
begin
   commit tran mytran
end