Question

I have a unique index set up in tblCombined. It is set up on the fields called cyDate, dtlNr, and seq, in that order.

I have another table – a staging table – called tblDailyResults. It has the exact same fields as tblCombined, but no index. Each day, I receive records into this staging table from a feed.

What I’d like to do is setup a “catch” if you will, so that if a duplicate record that violates the unique index, it won’t error out – rather, it will just not be inserted; it will remain in the staging table (I can then send out an alert noting such and manage it from there).

This is what I’ve tried:

   Insert Into tblCombined
    ( 
        cyDate      
        ,dtlNr
        ,seq
        ,chCode
        ,opCode
        ,nrCode

    )

    Select
        cyDate      
        ,dtlNr
        ,seq
        ,chCode
        ,opCode
        ,nrCode

    From tblDailyResults

    Where Not Exists (Select cyDate ,dtlNr ,seq From tblCombined)

But, this doesn’t seem to be working. I tested out a couple of records – changing the fields from what was already inserted, and it still excludes the non-duplicate records. I admit I’m new to using “not exists” so perhaps I’m not using it correctly.

I also tried Where Not In, but that doesn’t seem to work for multiple columns.

Any suggestions is appreciated. Thanks!

Answer 1

you need a where in the not exists part too, like …

where not exists (select 1 from tblcombined 
  where tblcombined.cydate = tbldailyresults.cydate 
  and tblcombined.dtlnr = tbldailyresults.dtlnr 
  and tblcombined.seq = tbldailyresults.seq)