Beefy Boxes and Bandwidth Generously Provided by pair Networks
Do you know where your variables are?

Comment on

( #3333=superdoc: print w/replies, xml ) Need Help??
First let me say that this is not flame bait. I can only comment on Oracle, but these results should not be considered useful against any other database besides MySQL. I'll save the gritty details unless anyone wants to hear about them.

One issue that I've not seen mentioned here is whether the database lives on the same machine as the code you're executing. I'm assuming it does, or you have a very fast network, or you have a small set of data. This is because if you were running on another machine your query would have to return the result set over the network, which could take a long time depending on the size of your data. One million rows * 1kB is much larger than a single count of the rows.

Another optimization you may want to test out would be to try doing a SELECT COUNT(1) FROM TABLE WHERE BLAH this will return the same result as COUNT(*) but may run faster depending on what kind of optimizations are done. This can be faster because we're not asking the database to return rows from the table, just the count. An old oracle trick until they internally optimized COUNT(*)


In reply to Re: How to count rows using DBI & mysql - Performance results by elwarren
in thread How to count rows using DBI & mysql - Performance results by Brovnik

Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":

  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?

    What's my password?
    Create A New User
    and all is quiet...

    How do I use this? | Other CB clients
    Other Users?
    Others having an uproarious good time at the Monastery: (5)
    As of 2018-06-20 02:19 GMT
    Find Nodes?
      Voting Booth?
      Should cpanminus be part of the standard Perl release?

      Results (116 votes). Check out past polls.