This response has nothing to do with Perl, but you should be able to process your data with one insert and one update statement. One would be of the form 
UPDATE real_table R
SET (col1, col2, col3,...)
  = SELECT col1, col2, col3,...
    FROM scratch S
    WHERE R.key_val1 = S.key_val1 AND R.key_val2 = S.key_val2 AND ...
;

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and the other would be like 
INSERT INTO real_table R
SELECT * FROM scratch S
WHERE NOT EXISTS (
  SELECT 1 FROM real_table
  WHERE key_val1 = S.key_val1 AND key_val2 = S.key_val2 AND ...
)

[download]
The snag with that sounds like some of the inserts might fail (since you mention skipping). At least you should be able to do the UPDATE, and delete those records. Then you can loop through what's left for INSERT/SKIP.
Caution: Contents may have been coded under pressure.

In reply to Re: Superior way to update SQL tables by Roy Johnson
in thread Superior way to update SQL tables by radiantmatrix

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