Question

我基本上尝试在某些表的多个列上执行相同的过程。我有程序，以及访问每列的游标语句，但我不能将我的表作为变量传递给游标：

代码：

DECLARE @columnName varchar(200),
 @Table1 TABLE(
        [Code] [nvarchar](50) NOT NULL,
        [Name] [nvarchar](255) NOT NULL,
        [Value1] [nvarchar](50) NOT NULL,
        [Value2] [nvarchar](50) NOT NULL,
        [Value3] [nvarchar](50) NOT NULL
    ),
 @Table2 TABLE(
        [Code] [nvarchar](50) NOT NULL,
        [Name] [nvarchar](255) NOT NULL,
        [Value1] [nvarchar](50) NOT NULL
        [Value2] [nvarchar](50) NOT NULL,
        [Value3] [nvarchar](50) NOT NULL
    )
INSERT @Table1 EXEC ProcedureThatAddsData;
INSERT @Table2 EXEC ProcedureThatAddsData;
DECLARE col_cursor CURSOR FOR   

select c.name from sys.tables t inner join sys.columns c on t.object_id = c.object_id where t.name = 'MySpecificTable'

OPEN col_cursor  

FETCH NEXT FROM col_cursor   
INTO @columnName  

WHILE @@FETCH_STATUS = 0  
BEGIN  
    PRINT @columnName
    --BEGIN BODY
    DECLARE @sql nvarchar(4000)


    set @sql = '
    INSERT INTO MySavedDifferencesTable
    select t1.Code, t1.Name, t1.'+ @columnName +' as OldValue, t2.'+ @columnName +' as NewValue
    from '+@Table1+' t1
    join '+@Table2+' t2
        on  t1.Code = t2.Code
        and t1.Name = t2.Name
        WHERE ISNULL(t1.' + @columnName +','') != ISNULL(t2.' + @columnName +','')
    ';
    exec (@sql)



    --end BODY
    FETCH NEXT FROM col_cursor   
    INTO @columnName
END   
CLOSE col_cursor;  
DEALLOCATE col_cursor;

如何使此过程正常工作。游标中的列选择正在工作，因此@columnName将遍历MySpecificTable中存在的所有列，但我在游标中传递2个表变量时遇到问题（for循环？）。

编辑：

这是我尝试添加到光标的部分：

@Table1 TABLE(
            [Code] [nvarchar](50) NOT NULL,
            [Name] [nvarchar](255) NOT NULL,
            [Value1] [nvarchar](50) NOT NULL,
            [Value2] [nvarchar](50) NOT NULL,
            [Value3] [nvarchar](50) NOT NULL
        ),
     @Table2 TABLE(
            [Code] [nvarchar](50) NOT NULL,
            [Name] [nvarchar](255) NOT NULL,
            [Value1] [nvarchar](50) NOT NULL
            [Value2] [nvarchar](50) NOT NULL,
            [Value3] [nvarchar](50) NOT NULL
        )
    INSERT @Table1 EXEC ProcedureThatAddsData;
    INSERT @Table2 EXEC ProcedureThatAddsData;

声明临时表变量并在游标内插入数据，或者以某种方式在游标内部传递已经充满数据的临时表。

Answer 1

我最终做的是创建一个临时表

-- check if temporary table already exists
    -- if not create it
    IF OBJECT_ID('tempdb..#MyTempTable') IS NULL
    begin
    --table with same columns as snapshot table to insert current data
    --MyTempTable
        CREATE TABLE #MyTempTable(
        [Code] [nvarchar](50) NOT NULL,..
    )
    end

    --remove old data if it exists from the temporary MyTempTable table
    delete from #MyTempTable;
    --insert the current data into the temporary MyTempTable table
    INSERT #SSDEStudySpecific EXEC procThatinsertsData;

现在我更新了在光标内部执行的sql：

set @sql = '
    INSERT INTO MySavedDifferencesTable
    select t1.Code, t1.Name, t1.'+ @columnName +' as OldValue, t2.'+ @columnName +' as NewValue
    from '+#MyTempTable1+' t1
    join SomeSystemTable t2
        on  t1.Code = t2.Code
        and t1.Name = t2.Name
        WHERE ISNULL(t1.' + @columnName +','') != ISNULL(t2.' + @columnName +','')
    ';

将2个表作为游标内的参数传递

1 个答案: