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bi89405
Starting Member
35 Posts |
 Posted - 2012-04-13 : 09:25:17
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| I have 3 tables.Table A, Table B, and Table C.Table A contains ID, Table B contains ID, and Table C contains IDa, and IDb.I want to create a link between A and B on ID BUT if A does not have a corresponding ID in B, then go to C link on IDa and use IDb to link to B.Does that make sense?Thanks in advance! |
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yosiasz
Master Smack Fu Yak Hacker
1635 Posts |
Posted - 2012-04-13 : 10:55:40
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| before offering a solution just curious why does this scenario exist in the first place?<><><><><><><><><><><><><><><><><>If you don't have the passion to help people, you have no passion |
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bi89405
Starting Member
35 Posts |
Posted - 2012-04-13 : 11:38:35
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| Table A is coming from one data source and table B is coming from another data source. Table C is the mapping table b/c some account codes in Table A are not the same as those found in Table B. We need Table C to help us determine which IDb field the account maps to. Does that make sense? |
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visakh16
Very Important crosS Applying yaK Herder
52326 Posts |
Posted - 2012-04-13 : 11:59:14
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| if C is table which represents relationship between A and B why not always use it for linking A and B? Whats the purpose of direct linking between A and B then if referential integrity is not maintained between them always?------------------------------------------------------------------------------------------------------SQL Server MVPhttp://visakhm.blogspot.com/ |
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Bustaz Kool
Master Smack Fu Yak Hacker
1834 Posts |
Posted - 2012-04-13 : 12:14:15
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| [CODE]select a.*, coalesce(b.Column, b2.Column) as Columnfrom TableA aleft outer join TableB b on a.id = b.idleft outer join TableC c on a.id = c.idAleft outer join TableB b2 on b2.id = c.idB[/CODE]You'll need to coalesce any column you want returned from the B/B2 table.=================================================There is a foolish corner in the brain of the wisest man. -Aristotle, philosopher (384-322 BCE) |
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