#36278 [Fbk->Opn]: extremely slow bytea extraction from pgsql
| From: | support at kalador dot com | Date: | Fri, 03 Feb 2006 21:38:19 +0000 |
| Subject: | #36278 [Fbk->Opn]: extremely slow bytea extraction from pgsql | ||
| References: | 1 | Groups: | php.bugs |
| Request: | Send a blank email to php-bugs+get-92880@lists.php.net to get a copy of this message | ||
ID: 36278
User updated by: support at kalador dot com
Reported By: support at kalador dot com
-Status: Feedback
+Status: Open
Bug Type: Performance problem
Operating System: redhat linux
PHP Version: 5.1.2
New Comment:
libpq is 3.2
Using postgresql 8.0.1 btw
Previous Comments:
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[2006-02-03 22:17:26] tony2001@php.net
What version of libpq are you using?
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[2006-02-03 21:34:53] support at kalador dot com
Description:
------------
I tried 3 ways to store big images (500K) in database and display in
browser. lo works fast, as does using a "text" column and converting
the image to base64 (and back for display). However, using bytea with
escaping is very slow.
Adding to the database is fine (it is fast), retrieving is the
problem.
Reproduce code:
---------------
This code consumed my CPU and took 77 seconds to run for a 400K image:
<?php
// Connect to the database
$dbconn = pg_connect('dbname=imagedb');
// Get the bytea data
$res = pg_query("SELECT data FROM image WHERE name='big.gif'");
// Convert to binary and send to the browser
header('Content-type: image/gif');
echo pg_unescape_bytea( pg_fetch_result($res,'data') );
?>
Expected result:
----------------
This should take less than 1 second. Using a text column and base64
escaping rather than a bytea column and pg_unescape_bytea takes less
than 1 second on the same data.
Actual result:
--------------
Actually result - 77 seconds.
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Edit this bug report at http://bugs.php.net/?id=36278&edit=1