FieldMapping not valid for MatchingMappings

Adamant22Adamant22 Posts: 2
edited February 25, 2015 12:39PM in SQL Data Compare Previous Versions
Anyone ever seen this message?
This happens on the Mapping step when comparing the databases.

I ran SQL Compare first and the database structure is the same.


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    Brian DonahueBrian Donahue Posts: 6,590 Bronze 1
    As far as I know, this exception should not happen in SQL Data Compare because it should prevent you from being able to map columns that can't be compared because of a difference in the datatype.

    Usually I see this message coming from SQL Comparison SDK apps. If you are using DataCompare.Engine.dll, I'd suggest throwing in some logic to check the MappingStatus field of every column mapping before you proceed to the comparison phase.
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    Brian DonahueBrian Donahue Posts: 6,590 Bronze 1
    The problem turned out to be with Data Compare after all, and the fix was to create a new project. The old project had some outdated schema information after some column datatypes had been changed.

    Normally this wouldn't cause a problem so I suspect maybe the project had been created in an older version of Data Compare, but I've got no way of checking that.
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    I still get this error in SQL Data Compare

    In the past, I've just created a new project. It is tiresome to re-discover the various settings I had set for comparing certain database pairs.
    Perhaps the product could give a more descriptive message, such as which table or column, or what we can do about it?
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    tschlarmtschlarm Posts: 23 Bronze 2
    This error is still present in
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    We were receiving the same error and found that it was due to a single table that had changed schema and the comparison file no longer could reconcile the mappings. To fix, you can open the .sdc file in a text editor (I recommend Notepad++) and cut out the bad table nodes. Then you can open the file in RedGate, re-select the table, and re-compare. Hope this helps!

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    I found and easier fix open,don't open by program but by SSMS select source and target the launch data compare it seems to create the project from there OK.

    This caused a few hours of frustration.
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    dei401dei401 Posts: 5 Bronze 1
    Thank you for your comment Brian Donahue » Mon Aug 08, 2011 11:26 am. This solved my issue.
    SQL Data Compare Standard Edition
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