[英]SQL Server subquery/CTE advice
I have a SQL query that runs sub 1 second:我有一个运行不到 1 秒的 SQL 查询:
SELECT
GB_BR_NAME AS 'Branch',
VM_VT_DESC AS 'VType',
S.VM_SK_VEHICLE AS 'Vehicle',
VM_SK_SEQUENCE AS 'Vehicle Sequence',
CASE
WHEN VM_VT_NU = 'N' THEN VM_SK_CONSTOTAL
WHEN VM_VT_NU = 'U' THEN VM_SK_ADJSTOCK
END AS 'Stock Value',
VM_SK_CONSTOTAL AS 'Cons Total',
VM_SK_ADJSTOCK AS 'Adj Total',
DD_MA_DESC AS 'Manufacturer',
DD_CL_DESCRIPTION AS 'Variant Class',
VM_VT_NU AS 'New/Used',
CASE
WHEN VM_EN_PROGRESS = 'Inv' THEN 'Y'
WHEN VM_EN_PROGRESS = 'Con' THEN 'Y'
ELSE 'N'
END AS 'Sold',
VM_SK_INTFREEDATE AS 'Interest Free Date',
CASE
WHEN VM_SK_INTFREEDATE <= GETDATE() AND DD_MA_DESC NOT IN ('Toyota', 'Skoda', 'Lexus', 'Honda') THEN 1
ELSE 0
END AS 'Interest Bearing',
VM_SK_STATUS AS 'Status'
FROM
VM_01_STOCK S
LEFT OUTER JOIN GB_00_BRANC B ON S.VM_SK_BRANCH = B.GB_BR_BRANCH
LEFT OUTER JOIN VM_01_VTYPE V ON S.VM_SK_VTYPE = V.VM_VT_VTYPE
LEFT OUTER JOIN VM_00_VEHICLE VE ON S.VM_SK_VEHICLE = VE.VM_VE_VEHICLE
LEFT OUTER JOIN DD_00_MANUF DDM ON VE.VM_VE_MANUFACT = DDM.DD_MA_MANUFACT
LEFT OUTER JOIN VM_01_SORDER SO ON S.VM_SK_VEHICLE = SO.VM_SO_VEHICLE AND S.VM_SK_SEQUENCE = SO.VM_SO_SEQUENCE
LEFT OUTER JOIN DD_00_VARCLASS CL ON VE.VM_VE_VARCLASS = CL.DD_CL_CODE
LEFT OUTER JOIN VM_01_ENQUIRY E ON S.VM_SK_ENQUIRY = E.VM_EN_ENQUIRY
WHERE
(VM_SK_STATUS = 'A' OR VM_SK_STATUS = 'C')
This outputs ~8000 rows.这会输出约 8000 行。
I then have a CTE which outputs ~40 rows.然后我有一个输出约 40 行的 CTE。 This also runs sub 1 second -这也运行不到 1 秒 -
WITH cte (VM_SK_VEHICLE) AS
(SELECT VM_SK_VEHICLE
FROM VM_01_STOCK SS LEFT OUTER JOIN VM_01_VTYPE V ON SS.VM_SK_VTYPE = V.VM_VT_VTYPE LEFT OUTER JOIN VM_00_VEHICLE VE ON SS.VM_SK_VEHICLE = VE.VM_VE_VEHICLE LEFT OUTER JOIN DD_00_VARCLASS CL ON VE.VM_VE_VARCLASS = CL.DD_CL_CODE LEFT OUTER JOIN NL_01_TRANS T ON LTRIM(RTRIM(str(VM_SK_VEHICLE))) + LTRIM(RTRIM(str(VM_SK_SEQUENCE))) = NL_TR_SUFFIX LEFT OUTER JOIN PL_01_TRANS PT ON NL_TR_DAYBOOK = PL_TX_DBNUM AND NL_TR_ITEM = PL_TX_DBITEM LEFT OUTER JOIN VM_01_VSPEC VP ON VM_SK_VEHICLE = VM_VS_VEHICLE
WHERE (VM_SK_STATUS = 'A' OR VM_SK_STATUS = 'C') AND VM_VT_NU = 'N' AND DD_CL_CODE IN ('CAR', 'LCV', 'HGV') AND VM_VS_DESC = 'Vehicle Price' AND VM_VS_ACTCOST <> 0.00
GROUP BY VM_SK_VEHICLE, VM_SK_SEQUENCE, VM_SK_CONSTOTAL
HAVING SUM(PL_TX_BASEVAL - PL_TX_BASEPAID) < (VM_SK_CONSTOTAL/2))
When I add to my main query当我添加到我的主查询时
CASE
WHEN S.VM_SK_VEHICLE IN (SELECT cte.VM_SK_VEHICLE FROM cte) THEN 1
ELSE 0
END AS 'Fully Paid',
it takes ~15 minutes to start showing results.开始显示结果大约需要 15 分钟。 I'm doing a LEFT JOIN to join CTE to my main query.我正在做一个 LEFT JOIN 将 CTE 加入我的主查询。
I've also tried this with a subquery which took ~37 minutes to start showing results.我还尝试了一个子查询,该子查询需要大约 37 分钟才能开始显示结果。
What do I need to do to get it running at proper speeds?我需要做什么才能让它以适当的速度运行?
Thank you.谢谢你。
The trouble seems to appear with this predicate:这个谓词似乎出现了问题:
LTRIM(RTRIM(STR(VM_SK_VEHICLE))) + LTRIM(RTRIM(STR(VM_SK_SEQUENCE))) = NL_TR_SUFFIX
Which is not sargable at all.这根本不是可悲的。
Create a computed persistent column with this expression:使用此表达式创建一个计算的持久列:
ALTER TABLE ??? ADD VM_SK_VEHICLE_SEQUENCE
AS LTRIM(RTRIM(STR(VM_SK_VEHICLE))) + LTRIM(RTRIM(STR(VM_SK_SEQUENCE))) PERSISTED
If you are in a recent version of SQL Server replace "LTRIM(RTRIM(" by "TRIM("如果您使用的是 SQL 服务器的最新版本,请将“LTRIM(RTRIM(”) 替换为“TRIM(”
Also, create a new index for the joined part...另外,为连接部分创建一个新索引...
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.