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MySql Data Restore

I recently had to restore a backup and to say the least it went bad.  I have missing records.  I now have two tables one is a good backup of the originally lost data (loanFindingReplace) and a live table that has some, but not all of the original findings.  I can not just replace the current live table (loanFinding) since I have had number entries since the restore.  How is the easiest/quickest query to determine which records don't exist in the loanFinding table that do exist in the loanFindingReplace table and insert those into loanFinding?  Both tables have the same fields with the same names.  Fields
Thank you.
0
rcowen00
Asked:
rcowen00
1 Solution
 
Kevin CrossChief Technology OfficerCommented:
Hi.

Sorry to hear about the failed restore. That can be a pain in the tail. To answer your question, I would start with a NOT EXISTS clause.

It works in general as:

SELECT {column list}
FROM TableA
WHERE NOT EXISTS (
   -- don't need to actually return data, so literal 1 is fine.
   SELECT 1 
   FROM TableB
   WHERE TableB.UniqueColumn = TableA.UniqueColumn
)
;

Open in new window


In your case, that may look like:
SELECT loanFindingKey
FROM loanFindingReplace r
WHERE NOT EXISTS (
   SELECT 1
   FROM loanFinding l
   WHERE l.loanFindingKey = r.loanFindingKey
)
;

Open in new window


Note: you may need to look at some other data that identifies a match if it is possible that you have duplicate auto_number values for non-matching rows due to the data lost. If not, then should be as simple as above.

Hopefully that helps!

Kevin
0
 
rcowen00Author Commented:
Thank you.
0

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