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Re: PSQL and many queries

by citycrew (Acolyte)
on Mar 24, 2009 at 01:12 UTC ( #752764=note: print w/replies, xml ) Need Help??


in reply to PSQL and many queries

Thanks for the feedback guys!

fzellinger:
The database and code will be on the same machine. Sorry for the broad criteria, I should have just put in the ceiling values. They could get very high which is where I needed the feedback.

My first thoughts were to use the system memory to load data file lines into a hash and load the DB records into an array (or visa versa) and check against each other. My hesitation on that was the memory load if the lists are large and more than one user runs this script

I like the idea in dumping the data files names into a table and querying against that!

I'll look into doing both solutions. If the data file and database isn't that large, I'll load it into memory with hashes, or I'll dump it into a table and query against it.

tilly, your approaches will take me a few days to process, maybe i could write a script to help me process your solutions quicker.. =o) great food for thought

Thanks again for the feedback!

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Re^2: PSQL and many queries
by BrowserUk (Pope) on Mar 24, 2009 at 01:27 UTC
    My first thoughts were to use the system memory to load data file lines into a hash and load the DB records into an array (or visa versa) and check against each other. My hesitation on that was the memory load if the lists are large and more than one user runs this script

    There's no need to load all of both datasets into memory.

    If you load the names from the DB into a hash (which DBI will do for you in one hit--select names from table; fetchall_hashref), then you can process your file line by line.


    Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
    "Science is about questioning the status quo. Questioning authority".
    In the absence of evidence, opinion is indistinguishable from prejudice.
      There's no need to load all of both datasets into memory. If you load the names from the DB into a hash (which DBI will do for you in one hit--select names from table; fetchall_hashref), then you can process your file line by line.

      Of course!.. thanks BrowserUk

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