No my friend , i didnt missed the Tachyon comment about the vec function..but the deprecated's code help me to understand what is going on with this function..

For the SQL command that you propose i want to ask you for which server is appropriate because on MySQL there is no command for the intersection( i tried some inner join but the perfomance was very very very slow for 1GB dataset (250000 pages,Average document length : 602 words Number of unique words: 907806)...

About your code for the Elias technique i have to say that it is 3 times faster than mine (Thanks one more time!!!)...The only reason why i want to use compression in my index is for perfomance reasons..that was my thougths untill now but it seems that i wasnt right..:(..since with the vec function i can decode 3000000 doc ids in 2 seconds and 10 milion in 6 secs!!!) as the below code shows..

use strict;
use Devel::Size qw(size);

my $wektor = '';
for(0 .. 10000000)
{
   vec ($wektor, $_, 32) = $_;
    
}
print "Vector's size: " .
  size( $wektor ) . " bytes\n";


my @vec;
my $Aa=time();

for(0 .. 10000000)
{
    push @vec,vec ($wektor, $_, 32);
}
print "unpack vector in \t",time()-$Aa,"  secs...(oh Yeah!!!)\n";

[download]
Size of  vector is 40000032 bytes

unpack vector in  6 secs...(oh Yeah!!!)

[download]
In the above code i used 4 bytes for each doc id. I tried with a vector where i save the same number of doc ids but with only 1 byte for each doc id ( i saved only small numbers) and the time was completely the same..I cant understand why..DOes anyone??

In reply to Re^3: Do you really want to use an array there? by MimisIVI
in thread Do you really want to use an array there? by deprecated

Title:
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, details, 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, summary, 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.