使用从临时表派生的值循环访问sql server表

问题描述 投票:1回答:1

我需要使用从临时表派生的值,并将其用作标准。请看我的代码:

declare @laneNum int
declare @startDate date = '2019-02-07'
declare @class int = 1
declare @id int 

if OBJECT_ID('tempdb..#tempLaneNumber') IS NOT NULL
drop table [#tempLaneNumber]

create table #tempLaneNumber
(
    LANE_NUMBER INT NULL
)


INSERT INTO #tempLaneNumber (LANE_NUMBER)
SELECT DISTINCT EXIT_LANE
FROM [dbo].[TOLL] 
ORDER BY EXIT_LANE ASC

select * from #tempLaneNumber

set @laneNum = (select * from #tempLaneNumber)

begin
    select COUNT(*)
    from [dbo].[TOLL]
    where convert(date, TRXN_DTIME) = @startDate and EXIT_LANE = @laneNum
end

如果我跑到select * from #tempLaneNumber我得到这个结果:

enter image description here

但是如果我在where语句中使用这个值作为标准,在begin语句中,我没有得到我预期的结果。

sql sql-server
1个回答
1
投票

您需要更改您的查询,如下所示。

select l.LANE_NUMBER, COUNT(*)
    from [dbo].[TOLL] t
    inner join  #tempLaneNumber l on t.EXIT_LANE = l.LANE_NUMBER
    where convert(date, TRXN_DTIME) = @startDate 
    GROUP BY l.LANE_NUMBER

您的查询中存在多个问题,我已经对这些问题进行了评论并在需要时进行了修改。

--declare @laneNum int [NOT REQUIRED]
declare @startDate date = '2019-02-07'
declare @class int = 1
declare @id int 

if OBJECT_ID('tempdb..#tempLaneNumber') IS NOT NULL
drop table [#tempLaneNumber]

create table #tempLaneNumber
(
    LANE_NUMBER INT NULL
)


INSERT INTO #tempLaneNumber (LANE_NUMBER)
SELECT DISTINCT EXIT_LANE
FROM [dbo].[TOLL] 
--ORDER BY EXIT_LANE ASC [NOT REQUIRED FOR INSERT]

select * from #tempLaneNumber

--set @laneNum = (select * from #tempLaneNumber) [YOU CAN'T ASSING A TABLE OUTPUT TO A INT VARIABLE]

--begin [NOT REQUIRED]
/*
    select COUNT(*)
    from [dbo].[TOLL]
    where convert(date, TRXN_DTIME) = @startDate and EXIT_LANE = @laneNum
*/
--CHANGED
select l.LANE_NUMBER, COUNT(*)
    from [dbo].[TOLL] t
    inner join  #tempLaneNumber l on t.EXIT_LANE = l.LANE_NUMBER
    where convert(date, TRXN_DTIME) = @startDate 
    GROUP BY l.LANE_NUMBER
--end [NOT REQUIRED]
© www.soinside.com 2019 - 2024. All rights reserved.