Full Text Indexing...

From: Chris Gamache <cgg007(at)yahoo(dot)com>
To: pgsql-general(at)postgresql(dot)org
Subject: Full Text Indexing...
Date: 2002-02-12 20:17:18
Message-ID: 20020212201718.36607.qmail@web13808.mail.yahoo.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

Computing the amount of disk space it would take to house the full text index
on one of the fields in my database:

36 bytes: each row header (approximate)
+ 53 bytes Varchar(53)
+ 8 bytes: oid field
+ 4 bytes: pointer on page to tuple
----------------------------------------
101 bytes per row

The data page size in PostgreSQL is 8192 bytes (8 KB), so:

8192 bytes per page
------------------- = 82 rows per database page (rounded up)
101 bytes per row

561062644 data rows
-------------------- = 6842228 database pages
82 rows per page

6842228 database pages * 8192 bytes per page = 56,051,531,776 bytes (56 GB)

Is my math right??? WOW! This thing is HUUUGE!

Table "title_fti"
Attribute | Type | Modifier
-----------+-----------------------+----------
string | character varying(53) |
id | oid |

When I index the oid, and the string,oid I'll get roughly another 75-100MB,
yes?

Ayn tips/tricks, or am I just going to have to add another 100MB to my server?

CG

__________________________________________________
Do You Yahoo!?
Send FREE Valentine eCards with Yahoo! Greetings!
http://greetings.yahoo.com

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Jeff Self 2002-02-12 21:00:54 Re: First time installer !!
Previous Message Chris Gamache 2002-02-12 20:02:32 Re: 7.1.3 : copy from stdin is very slow!