Question

我试图删除除2个表之外的所有非系统表。但它总是删除所有的表格。

这段代码我做错了什么？

/* Drop all tables */
DECLARE @name VARCHAR(128)
DECLARE @SQL VARCHAR(254)

SELECT @name = (SELECT TOP 1 [name] 
                    FROM sysobjects 
                    WHERE [type] = 'U' 
                      AND category = 0  
                      AND name NOT IN ('JobSource', 'City') 
                    ORDER BY [name])

WHILE @name IS NOT NULL
BEGIN
   SELECT @SQL = 'DROP TABLE [dbo].[' + RTRIM(@name) +']'

   EXEC (@SQL)
   PRINT 'Dropped Table: ' + @name

   SELECT @name = (SELECT TOP 1 [name] 
                   FROM sysobjects 
                   WHERE [type] = 'U' 
                     AND category = 0 
                     AND [name] > @name 
                   ORDER BY [name])
END

Answer 1

当您在结尾处更新@name变量时，您忘记将名称条件添加到内循环的WHERE子句中。

像这样改变你的循环（注意最后的SELECT语句）：

WHILE @name IS NOT NULL
BEGIN
    SELECT @SQL = 'DROP TABLE [dbo].[' + RTRIM(@name) +']'
    EXEC (@SQL)
    PRINT 'Dropped Table: ' + @name
    SELECT @name = (SELECT TOP 1 [name] FROM sysobjects WHERE [type] = 'U' AND category = 0 and name not in ('JobSource', 'City') ORDER BY [name])
END

另外，你可能不需要该子句中的AND [name] > @name所以我把它拿出来了。

SQL Server：删除所有非系统表除外？

1 个答案: