Beefy Boxes and Bandwidth Generously Provided by pair Networks
go ahead... be a heretic
 
PerlMonks  

comment on

( [id://3333] : superdoc . print w/replies, xml ) Need Help??

Just a note that index implementations vary widely from platform to platform. As others have pointed out above, PG and Oracle (among others) implement function indexes. Some others won't use an index on that query at all because of the less-than condition.

The key thing to note is that indexes are not "magic". Some programmers seem to believe that whenever a column is involved in a query, adding an index will make the query faster. This is rarely true. As in optimizing your Perl code, you should measure, measure, and measure again, then make a choice based on that.


In reply to Re: (OT) Don't blow that index dude. by VSarkiss
in thread (OT) Don't blow that index dude. by demerphq

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



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or How to display code and escape characters are good places to start.