Question

我正在运行以下查询无法正常运行：

create table #temp(
 tableName nvarchar(50)
)
insert into #temp
SELECT TABLE_NAME 
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'
DECLARE @name VARCHAR(50)
DECLARE @TQ VARCHAR(500)
DECLARE @ContainName VARCHAR(500)
DECLARE db_cursor CURSOR FOR  
SELECT tableName 
FROM #temp

OPEN db_cursor   
FETCH NEXT FROM db_cursor INTO @name   

WHILE @@FETCH_STATUS = 0   
BEGIN   
      select @name IF COL_LENGTH(@name,'IsDeleted') IS NOT NULL
      begin
        IF COL_LENGTH(@name,'IsActive') IS NOT NULL
        begin
            exec ('UPDATE '+@name+' SET  [IsActive] = ~[IsDeleted]')

        end      
        ELSE
        BEGIN
            exec('ALTER TABLE '+@name+' ADD IsActive bit')
            exec ('UPDATE '+@name+' SET  [IsActive] = ~[IsDeleted]')
            exec('ALTER TABLE '+@name+' ALTER COLUMN IsActive SET DEFAULT ''true''')

        END
        if exists(select * from sysobjects o inner join syscolumns c on o.id = c.cdefault inner join sysobjects t on c.id = t.id where o.xtype = 'D' and c.name = 'IsDeleted' and t.name = @name)
            begin
                set @ContainName=(select o.name from sysobjects o inner join syscolumns c on o.id = c.cdefault inner join sysobjects t on c.id = t.id where o.xtype = 'D' and c.name = 'IsDeleted' and t.name = @name)
                exec('ALTER TABLE ' + @name + ' drop constraint ' + @ContainName)
            end
        exec('ALTER TABLE '+@name+' DROP COLUMN [IsDeleted]')
      end

      FETCH NEXT FROM db_cursor INTO @name   
END   

CLOSE db_cursor   
DEALLOCATE db_cursor


drop table #temp

在我的db中的大多数表中，有两列“IsActive”和“IsDeleted”，它们都具有默认键约束和BIT类型我想做以下事情：

如果存在列IsDeleted，请将其IsDeleted的负值复制到IsActive。
如果列IsDeleted存在但不存在IsActive，则创建列IsActive，将IsDeleted的负值复制到IsActive，然后将默认键约束添加到列IsDeleted。

3.最后从列IsDeleted中删除默认值约束，然后删除该列。

我正在查询db中的每个表。上面的查询运行正常，并按我的意愿更新每个表，但它也给我错误'SET'附近的错误语法

我用4个表创建了测试数据库。第一个表有2列：IsActive和IsDeleted，第二个表只有列IsActive，第三个表只有列IsDeleted，第四个表有一个正常的nvarchar列。当执行上面。一切正常，但在SET附近收到错误语法错误。实际上我得到了所需的结果，但也收到了不需要的错误信息。

Answer 1

这对我有用：

DECLARE @name VARCHAR(50)
DECLARE @TQ VARCHAR(500)
DECLARE @ContainName VARCHAR(500)

DECLARE db_cursor CURSOR
FOR
    SELECT  TABLE_NAME
    FROM    INFORMATION_SCHEMA.TABLES
    WHERE   TABLE_TYPE = 'BASE TABLE'

OPEN db_cursor   
FETCH NEXT FROM db_cursor INTO @name   

WHILE @@FETCH_STATUS = 0
    BEGIN   
        IF COL_LENGTH(@name, 'IsDeleted') IS NOT NULL
            BEGIN
                IF COL_LENGTH(@name, 'IsActive') IS NOT NULL
                    BEGIN
                        EXEC ('UPDATE '+@name+' SET  [IsActive] = 1 - [IsDeleted]')
                    END      
                ELSE
                    BEGIN
                        EXEC('ALTER TABLE '+@name+' ADD IsActive bit')
                        EXEC ('UPDATE '+@name+' SET  [IsActive] = 1 - [IsDeleted]')
                        EXEC('ALTER TABLE '+@name+' ADD CONSTRAINT DF_'+@name+' DEFAULT(0) for [IsActive]')

                    END
                IF EXISTS ( SELECT  *
                            FROM    sysobjects o
                                    INNER JOIN syscolumns c ON o.id = c.cdefault
                                    INNER JOIN sysobjects t ON c.id = t.id
                            WHERE   o.xtype = 'D'
                                    AND c.name = 'IsDeleted'
                                    AND t.name = @name )
                    BEGIN
                        SET @ContainName = ( SELECT o.name
                                             FROM   sysobjects o
                                                    INNER JOIN syscolumns c ON o.id = c.cdefault
                                                    INNER JOIN sysobjects t ON c.id = t.id
                                             WHERE  o.xtype = 'D'
                                                    AND c.name = 'IsDeleted'
                                                    AND t.name = @name
                                           )
                        EXEC('ALTER TABLE ' + @name + ' drop constraint ' + @ContainName)
                    END
                EXEC('ALTER TABLE '+@name+' DROP COLUMN [IsDeleted]')
            END

        FETCH NEXT FROM db_cursor INTO @name   
    END   

CLOSE db_cursor   
DEALLOCATE db_cursor

获取错误“关键字'SET'附近的语法不正确。”在更新数据库表时

1 个答案: