Question

我尝试了两个查询来更新列

更新查询＃1：

DECLARE @Counter INT=0 --This causes the @@rowcount to be > 0

while @@rowcount>0
begin
   set rowcount 10000

   update r
   set Comp = t.Comp
   from [dbo].[Vente] r 
   inner join [dbo].tempBudgeT t with (index (index_Budget )) 
                 on t.[Code Site] = r.[Code Site]
                 and t.[Code Structure] = r.[Code Structure]
                 and t.[Date Time] = convert(date, r.[Date Time])
   where r.[Date Time] >= '2015-01-01 00:0:00.000'
     and r.Comp is null
end

SET rowcount 0

更新查询＃2：

 DECLARE @Counter INT=0 --This causes the @@rowcount to be > 0

 while @@rowcount > 0
 begin
     set rowcount 10000

     update [dbo].[Vente] 
     set Comp = (select top 1 t.comp
                 from [dbo].[Budget] t with (index (index_Budget))
                 where t.[Code Site] = [dbo].[Vente].[Code Site]
                   and t.[Code Rayon] = substring([dbo].[Vente].[Code Structure], 1, 4)
                   and t.[Date Time] = convert(date, [dbo].[Vente].[Date Time])
                   and [dbo].[Vente].[Date Time] >= '2015-01-01 00:0:00.000'
                   and [dbo].[Vente].Comp is null)
 end

 SET rowcount 0

我的问题是第二个查询比第一个查询更快但它没有工作，comp没有用第二个查询更新？问题在哪里？

Answer 1

您的[dbo].[Vente]和[dbo].[Budget]尚未加入，并在子查询中更新条件：

DECLARE @Counter INT = 0 --This causes the @@rowcount to be > 0

WHILE @@rowcount > 0
BEGIN
    SET ROWCOUNT 10000

    UPDATE v
    SET Comp = (
            SELECT TOP 1 t.comp
            FROM [dbo].[Vente] v
            INNER JOIN [dbo].[Budget] t WITH (INDEX (index_Budget)) t.[Code Site] = v.[Code Site]
            WHERE t.[Code Site] = v.[Code Site]
                AND t.[Code Rayon] = substring([dbo].[Vente].[Code Structure], 1, 4)
                AND t.[Date Time] = convert(DATE, [dbo].[Vente].[Date Time])
                AND [dbo].[Vente].[Date Time] >= '2015-01-01 00:0:00.000'
                AND [dbo].[Vente].Comp IS NULL
            )
END

SET ROWCOUNT 0

两个UPDATE查询

1 个答案: