How to avoid subquery here with this query , please...

  • Hello All Good Evening,

    Could you please help me with this query, how can i write this query without sub query, or how can write this query another ways

    please help me

    select planno, status1, count(*) Counts from

    (

    select a.ValetNO PlanNo ,

    case

    when JoinCode in ('00', '01', '02') then 'Actcess'

    when JoinCode in ('20', '21', '22', '23','38', '39') then

    'Secured'else 'Other' end Status1 ---, COUNT (*)

    from dbo.ppt a(NOLOCK) left join dbo.acts b on a.P_ID = b.P_ID and a.ValetNO = b.ValetNO

    --group by a.ValetNO

    )

    a group by planno, status1

    order by 2

    Thank you in Advance

    dhani

  • Why is the subquery a problem?

    It can be written without it, but probably won't change how the query executes.

    Gail Shaw
    Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
    SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

    We walk in the dark places no others will enter
    We stand on the bridge and no one may pass
  • You can use CTE if you dont want to use subquery...

    _______________________________________________________________
    To get quick answer follow this link:
    http://www.sqlservercentral.com/articles/Best+Practices/61537/

  • Please try code below. I didn't have any data to test it first, of course.

    SELECT

    a.ValetNO AS PlanNo,

    cross_apply_1.Status1,

    COUNT(*) AS Counts

    FROM dbo.ppt a WITH (NOLOCK)

    LEFT OUTER JOIN dbo.acts b ON

    b.P_ID = a.P_ID AND

    b.ValetNO = a.ValetNO

    CROSS APPLY (

    SELECT

    CASE

    WHEN b.JoinCode in ('00', '01', '02') THEN 'Actcess'

    WHEN b.JoinCode in ('20', '21', '22', '23','38', '39') THEN 'Secured'

    ELSE 'Other'

    END AS Status1

    ) AS cross_apply_1

    GROUP BY

    a.ValetNO,

    cross_apply_1.Status1

    ORDER BY

    Status1

    SQL DBA,SQL Server MVP(07, 08, 09) "It's a dog-eat-dog world, and I'm wearing Milk-Bone underwear." "Norm", on "Cheers". Also from "Cheers", from "Carla": "You need to know 3 things about Tortelli men: Tortelli men draw women like flies; Tortelli men treat women like flies; Tortelli men's brains are in their flies".

  • Hello Thank you for your reply,

    just want to know any otherway to do this,

    also would like to know effecient way to do it

    Thank you

    Dhani

  • I have 2 questions:

    1. Where is the subquery? I see a derived table.

    2. Are you sure you want to use NOLOCK? There's a lot of potential gotchas in there.


    My mantra: No loops! No CURSORs! No RBAR! Hoo-uh![/I]

    My thought question: Have you ever been told that your query runs too fast?

    My advice:
    INDEXing a poor-performing query is like putting sugar on cat food. Yeah, it probably tastes better but are you sure you want to eat it?
    The path of least resistance can be a slippery slope. Take care that fixing your fixes of fixes doesn't snowball and end up costing you more than fixing the root cause would have in the first place.

    Need to UNPIVOT? Why not CROSS APPLY VALUES instead?[/url]
    Since random numbers are too important to be left to chance, let's generate some![/url]
    Learn to understand recursive CTEs by example.[/url]
    [url url=http://www.sqlservercentral.com/articles/St

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