Dear monks,

I have a quite modest dataset of various financial data (high-frequency currency quotes over a course of years) at the size of around 15 GB. I used to keep it in plaintext files, but now I'd want to run some simple queries with it. Hence, I need a database. I tried MySQL, but 15 gigs seems to be too much for it, with indices in place. Therefore, I put in PostgreSQL.

Now to the question. The usual scenario for this database is going to be 'gimme a whole set of quotes for a certain few days for latter aggregation'. This gives me a resultset which amounts to hundreds of megabytes. It's obvious that I don't want to put it all into memory. At once. For every aggregation request (even with caching, it can be several requests per minute). So, I need a cursor. And guess what? Cursors seem to be not supported in DBD::Pg at all!

Can you enlighten me on the alternatives I have in this situation? Figure out how to use PL/perl? Use another database? Drop the database at all and stick to my beloved plain text data files? Something else? I'd really appreciate a solution.

In reply to PostgreSQL cursors with Perl. by atemerev

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