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KGOldWolf KGOldWolf is offline
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Default Array VLOOKUPs take 6 times longer than worksheet range VLOOKUPs

I can post the code but I am running compartive performance tests.

I read 10k rows that split to output 22k rows. During this I do 100k
VLOOKUPS. Posting output directly to worksheet took 12 seconds. Creating an
array and then moving all 22k records to a worksheet range took 10 second
(20% reduction in processing time).

So far so good.

I moved the lookup table off the worksheet into an array (60 rows * 8
columns).

Processing time INCREASED to 60 seconds (600% increase!)

I must be doing something wrong but before I go nuts tweaking the code I
would like to know if this surprises you or, are some functions (like
VLOOKUPS) inherently slower when used in arrays?

I didn't name the array as a table (couldn't figure out how to do that but
the VLOOKUPs functioned by referencing "Array_Dates" without fail - just slow.

Any comments? I can post the code but thought the general concept would be
okay.

Thanks,
KG