Question

我有一个包含用户定义字段的表，我希望根据另一个表保持更新。为了做到这一点，我创建了以下查询

select 
    a + b + c + d + e + f + g + h 
from
    (select 
         'update gl00100 set USERDEF1 =' as a, 
         '''' + DMA + '''' as b, 
         ', set USERDEF2 =' as c, 
         '''' + Brand + '''' as d, 
         ', set USRDEFS1 =' as e,
         '''' + convert(char(10), dateopened, 120) + '''' as f, 
         'where actnumbr_2 =' as g,
         GPStore as h  
     from 
         [192.168.xxx.xx].bi.dbo.store 
     where 
         store <> 0000 and DateOpened is not null) x

正如您所知，查询正在构建我想要运行的更新语句。如何运行查询然后运行结果。这甚至可能吗？

Answer 1

试试这个：

DECLARE @sql nvarchar(2000)
DECLARE #crs INSENSITIVE CURSOR FOR
SELECT 'update gl00100 set USERDEF1 =' as a, ''''+DMA+'''' as b, ', 
   set USERDEF2 =' as c, ''''+Brand+'''' as d, ', set USRDEFS1 =' as e,
   ''''+convert(char(10),dateopened,120)+'''' as f, 'where actnumbr_2 =' as g,
   GPStore as h  
from [192.168.xxx.xx].bi.dbo.store where store <> 0000 and DateOpened is not null 
OPEN #crs
FETCH NEXT FROM #crs INTO @sql
WHILE @@FETCH_STATUS = 0
BEGIN
    EXEC sp_executesql @sql
    FETCH NEXT FROM #crs INTO @sql
END
CLOSE #crs
DEALLOCATE #crs

Answer 2

您可以使用JOIN而不是构建动态SQL语句并逐个执行它们来执行此操作：

UPDATE  g
SET     USERDEF1 = s.DMA,
        USERDEF2 = s.Brand,
        USRDEFS1 = s.DateOpened
FROM    gl00100 AS g
        INNER JOIN [192.168.xxx.xx].bi.dbo.store AS s
            ON s.GPStore = g.actnumbr_2
WHERE   s.Store <> 0000 
AND     s.DateOpened IS NOT NULL;

您可能还会发现使用OPENQUERY可以获得更好的性能，当使用4个部分名称进行跨服务器查询时，您也无法利用统计信息，因此您最终可能无法使用整个存储表进入内存，最后只选择几行。所以你可能会尝试这样的事情：

UPDATE  g
SET     USERDEF1 = s.DMA,
        USERDEF2 = s.Brand,
        USRDEFS1 = s.DateOpened
FROM    gl00100 AS g
        INNER JOIN OPENQUERY
        (   [192.168.xxx.xx], 
            'SELECT DMA, Brand, DateOpened, GPStore 
            FROM bi.dbo.store 
            WHERE store <> 0000 AND DateOpened is not null'
        ) AS s
            ON s.GPStore = g.actnumbr_2

TSQL更新语句执行

2 个答案: