Two not so obvious advices.

1. batch the import. If the database you decide has some batch import tools able to handle your format, use them. Otherwise turn off AutoCommit when creating the DBI object and commit only once every thousand (ten thousands? ... that depends) records. This will speed the import up quite a bit.

2. make sure you define indexes on your tables. Not too few and not too many. If the database you choose allows you to see the "estimated execution plan" of the query generating the report, use that and make sure it doesn't use "table scans" on tables you only need a few rows from etc. Don't be afraid to play with this a bit, create an index, see what it does with the estimated execution plan and estimated price and see how long does it run ...

You may spend a lot of time with this at first, but as the management starts inventing more and more reports that they'd like, it will pay off.

Jenda
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In reply to Re^5: Invert a hash... not a FAQ (I hope) by Jenda
in thread Invert a hash... not a FAQ (I hope) by djacobow

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