Limitation in Joining Databases?

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idea_new_user
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Joined: 08/31/2017 - 05:23
Limitation in Joining Databases?

Hello,
 
I had joined a primary database to a secondary database using "Records with no secondary match" option where both databases have a common key.
 
After looking through the data in the joined database, I realised that some of these unmatched data to secondary database were found in secondary database.
 
So I re-joined the joined database to the same secondary database using "Records with no secondary match" option. And the output database had fewer records compared to the first join.
 
In this case, are there existing limitations in joining databases?
 
Thanks and Regards!

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Brian Element
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Joined: 07/11/2012 - 19:57

Hi idea_new_user,

That is strange.  I have never heard of that.  It has always worked with me.  So if you are joining a primary database to a secondary database and you select "Records with no secondary match" then the resulting database should have records from the primary file that do not have a match on the secondary database.  Now a place that might cause a problem is if you are using a virtual field, you create an index and then go and make a change to the virtual field and don't do a reindex, in that case your join would be on an incorrect index and you would have incorrect results.  Can you post some of the file as I would be interested to see it.

Thanks

Brian

idea_new_user
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Joined: 08/31/2017 - 05:23

Hello Brian,
 
As you had mentioned, I was indeed using virtual fields as common key to join primary DB to secondary DB. I had performed a re-index on the virtual fields and a re-join. And the output database was finally correct!
 
Thanks for helping, Brian!

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Brian Element
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Joined: 07/11/2012 - 19:57

Glad I could help, I have been caught a few times on this, using a virtual field and forgetting I am using an old index.

Good luck with your project.

Brian

idea_new_user
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Joined: 08/31/2017 - 05:23

Thanks, Brian!