Comments on: Getting “EXP-00091: Exporting questionable statistics.” error on Oracle export

By: deloeranguy

deloeranguy — Wed, 21 Oct 2009 22:04:10 +0000

You are right! I love this website!

Even though my boss ran the export on the same machine, he went back and did see a message about a character set not being the same, so the first guess was dead on.

My boss also believes he should analyze the tables after import, so that recommendation is dead on, too.

Thank you very much!

By: carlosdl

carlosdl — Wed, 21 Oct 2009 21:53:21 +0000

Oracle stores some statistics about objects (tables, indexes, etc…) which are used by the optimizer to choose the best execution plan for some operations. Those statistics include things like number of rows, number of distinct keys, etc…

By ‘questionable statistics’ it means that some statistics were included in the export operation, but they could be ‘inaccurate’, so it would be better to analyze the tables after importing the file into the database.

By: deloeranguy

deloeranguy — Wed, 21 Oct 2009 21:41:12 +0000

Oh and pardon me, he’s dumping the entire table with no WHERE clause…forgot to add that!

By: deloeranguy

deloeranguy — Wed, 21 Oct 2009 21:39:44 +0000

Thanks for the reply. I certainly appreciate that questions often come with little information. At your response, my boss clarified that he’s running the extract on the same machine as the database/server (it all runs on a laptob, btw). He’s run this extract before a couple of times, and once got a clean run (i.e., no messages) and once with this same message.

If we can ignore this message, great. I’m just curious what “questionable statistics” means…thanks!