Flatten rows in a join

  • I have a stored procedure that currently brings back one row per policy number. A new table has been introduced that needs to be joined to that stored procedure. That table currently has six entries per policy but that can increase or decrease. This is sort of what I am looking at.

    Although it is much more complex I think this will illustrate the issue:

    create table #Policies(PolicyNo int, SomeData Char(5))

    insert into #Policies(policyno,somedata) values (1,'abcd')

    create table #NewTable(PolicyNo int,NewData char(5),akey int)

    insert into #NewTable(PolicyNo,NewData,akey) values(1, 'aaaa',1)

    insert into #NewTable(PolicyNo,NewData,akey) values(1, 'bbbb',2)

    insert into #NewTable(PolicyNo,NewData,akey) values(1, 'cccc',3)

    insert into #NewTable(PolicyNo,NewData,akey) values(1, 'dddd',4)

    Lets say this is the current stored procedure:

    select * from #Policies p where policyno = 1

    I need to join #NewTable to it:

    select p.policyno,t.Newdata,t.akey from #Policies p

    join #NewTable t on t.policyno = p.policyno

    where p.policyno = 1

    But I need the output to look like this:

    PolicyNo NewData akey NewData akey NewData akey NewData akey

    1 aaaa 1 bbbb 2 cccc 3 dddd 4

    Any ideas assuming at this point I can't change the table structure. If the stored procdure always brought back one row I could flatten #NewTable first and join to that. The real issue is the stored procedure could bring back many policies and each one needs to be one row per policy with the #NewTable data flattened out per policy row

    EDIT #NewTable is dynamic so the number of entries is not fixed.

  • It looks like a dynamic crosstab query might help. Have a look here[/url] for an example.

    The absence of evidence is not evidence of absence
    - Martin Rees
    The absence of consumable DDL, sample data and desired results is, however, evidence of the absence of my response
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  • What I ended up doing just for expediency’s sake is:

    In the select:

    ,'GR' + convert(Varchar,t1.pkRate_Barcodes) 'ac2'

    ,'GR' + convert(Varchar,t2.pkRate_Barcodes) 'ac26'

    ,'GR' + convert(Varchar,t3.pkRate_Barcodes) 'GrpRatCont'

    ,'GR' + convert(Varchar,t4.pkRate_Barcodes) 'EnrollQuest'

    ,'GR' + convert(Varchar,t5.pkRate_Barcodes) 'EnrollQuestInv'

    ,'GR' + convert(Varchar,t6.pkRate_Barcodes) 'U-153'

    The join:

    join Rate_BarCodes t1 on gr.EstExperienceYear = t1.EstExperienceyear

    and ge.fkgroup = t1.fkgroup and t1.document_type_name = 'AC-2'

    and e.policyno = t1.policyno

    join Rate_BarCodes t2 on gr.EstExperienceYear = t2.EstExperienceyear

    and ge.fkgroup = t2.fkgroup and t2.document_type_name = 'AC-26'

    and e.policyno = t2.policyno

    join Rate_BarCodes t3 on gr.EstExperienceYear = t3.EstExperienceyear

    and ge.fkgroup = t3.fkgroup and t3.document_type_name = 'GrpRatCont'

    and e.policyno = t3.policyno

    join Rate_BarCodes t4 on gr.EstExperienceYear = t4.EstExperienceyear

    and ge.fkgroup = t4.fkgroup and t4.document_type_name = 'EnrollQuest'

    and e.policyno = t4.policyno

    join Rate_BarCodes t5 on gr.EstExperienceYear = t5.EstExperienceyear

    and ge.fkgroup = t5.fkgroup and t5.document_type_name = 'EnrollQuestInv'

    and e.policyno = t5.policyno

    join Rate_BarCodes t6 on gr.EstExperienceYear = t6.EstExperienceyear

    and ge.fkgroup = t6.fkgroup and t6.document_type_name = 'U-153'

    and e.policyno = t6.policyno

    I had left out part of the requirements. Each column name from the #NewTable had to have the column name in the select. That is becuase it needs to be exposed to Crystal reports.

    I didn't check into cross tabs or pivot.

    Thanks to those that replied.

  • I think it's ok that you write queries fast, but just remember that quickfixes sometimes end up stablished as final solution when there is better options available.

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