Question

当我尝试在游标循环中运行以下SQL代码段时，

set @cmd = N'exec sp_rename ' + @test + N',' +
           RIGHT(@test,LEN(@test)-3) + '_Pct' + N',''COLUMN'''

我收到以下消息，

Msg 15248，Level 11，State 1，Procedure sp_rename，Line 213
参数@objname不明确或声明@objtype（COLUMN）错误。

有什么问题，我该如何解决？我尝试用括号[]包装列名称，并像一些建议的搜索结果一样双引号""。

编辑1 -

这是整个脚本。如何将表名传递给重命名sp？我不知道如何做到这一点，因为列名在许多表之一。

BEGIN TRANSACTION

declare @cnt int
declare @test nvarchar(128)
declare @cmd nvarchar(500) 
declare Tests cursor for
SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE COLUMN_NAME LIKE 'pct%' AND TABLE_NAME LIKE 'TestData%'

open Tests
fetch next from Tests into @test
while @@fetch_status = 0
BEGIN
  set @cmd = N'exec sp_rename ' + @test + N',' + RIGHT(@test,LEN(@test)-3) + '_Pct' + N', column' 

  print @cmd

  EXEC sp_executeSQL @cmd

  fetch next from Tests into @test
END

close Tests 
deallocate Tests


ROLLBACK TRANSACTION
--COMMIT TRANSACTION

编辑2 - 该脚本旨在重命名名称与模式匹配的列，在本例中为“pct”前缀。列出现在数据库中的各种表中。所有表名都以“TestData”为前缀。

Answer 1

这是稍微修改过的版本。更改被注明为代码注释。

BEGIN TRANSACTION

declare @cnt int
declare @test nvarchar(128)
-- variable to hold table name
declare @tableName nvarchar(255)
declare @cmd nvarchar(500) 
-- local means the cursor name is private to this code
-- fast_forward enables some speed optimizations
declare Tests cursor local fast_forward for
 SELECT COLUMN_NAME, TABLE_NAME
   FROM INFORMATION_SCHEMA.COLUMNS 
  WHERE COLUMN_NAME LIKE 'pct%' 
    AND TABLE_NAME LIKE 'TestData%'

open Tests
-- Instead of fetching twice, I rather set up no-exit loop
while 1 = 1
BEGIN
  -- And then fetch
  fetch next from Tests into @test, @tableName
  -- And then, if no row is fetched, exit the loop
  if @@fetch_status <> 0
  begin
     break
  end
  -- Quotename is needed if you ever use special characters
  -- in table/column names. Spaces, reserved words etc.
  -- Other changes add apostrophes at right places.
  set @cmd = N'exec sp_rename ''' 
           + quotename(@tableName) 
           + '.' 
           + quotename(@test) 
           + N''',''' 
           + RIGHT(@test,LEN(@test)-3) 
           + '_Pct''' 
           + N', ''column''' 

  print @cmd

  EXEC sp_executeSQL @cmd
END

close Tests 
deallocate Tests

ROLLBACK TRANSACTION
--COMMIT TRANSACTION

如何获取多个列以用于游标循环？

1 个答案: