Bug #72736 [NEW]: Slow performance when fetching large dataset with mysqli / PDO
From: petr dot hrabal at gmail dot com
Operating system: Debian 8
PHP version: 7.0.9
Package: *Database Functions
Bug Type: Bug
Bug description:Slow performance when fetching large dataset with mysqli / PDO
Description:
------------
I have large MySQL query (1.8M rows, 25 columns - all string between 20
and 256 chars) and I need to make 2 dimensional array from it (memory
table based on primary key).
Code works as expected, but $table creation takes a long time in
PHP7.0.9 or 7.1.0-dev
same proble apears when PDO is used
more extensive info/diagnostics at
http://stackoverflow.com/questions/38614982/mysqli-fetch-assoc-performance-php5-4-vs-php7-0
with tested dataset PHP5.x performs 10 times faster
Test script:
---------------
$vysledek = mysqli_query ( $conn,"SELECT * FROM table WHERE 1");
while($zaznam = mysqli_fetch_assoc ( $vysledek )){
$table[$zaznam['prikey']] = $zaznam;
}
--
Edit bug report at https://bugs.php.net/bug.php?id=72736&edit=1
--
Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=72736&r=trysnapshot54
Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=72736&r=trysnapshot55
Try a snapshot (trunk): https://bugs.php.net/fix.php?id=72736&r=trysnapshottrunk
Fixed in SVN: https://bugs.php.net/fix.php?id=72736&r=fixed
Fixed in release: https://bugs.php.net/fix.php?id=72736&r=alreadyfixed
Need backtrace: https://bugs.php.net/fix.php?id=72736&r=needtrace
Need Reproduce Script: https://bugs.php.net/fix.php?id=72736&r=needscript
Try newer version: https://bugs.php.net/fix.php?id=72736&r=oldversion
Not developer issue: https://bugs.php.net/fix.php?id=72736&r=support
Expected behavior: https://bugs.php.net/fix.php?id=72736&r=notwrong
Not enough info: https://bugs.php.net/fix.php?id=72736&r=notenoughinfo
Submitted twice: https://bugs.php.net/fix.php?id=72736&r=submittedtwice
register_globals: https://bugs.php.net/fix.php?id=72736&r=globals
PHP 4 support discontinued: https://bugs.php.net/fix.php?id=72736&r=php4
Daylight Savings: https://bugs.php.net/fix.php?id=72736&r=dst
IIS Stability: https://bugs.php.net/fix.php?id=72736&r=isapi
Install GNU Sed: https://bugs.php.net/fix.php?id=72736&r=gnused
Floating point limitations: https://bugs.php.net/fix.php?id=72736&r=float
No Zend Extensions: https://bugs.php.net/fix.php?id=72736&r=nozend
MySQL Configuration Error: https://bugs.php.net/fix.php?id=72736&r=mysqlcfg
Thread (9 messages)
- petr dot hrabal at gmail dot com