From: ssufficool at gmail dot com
Operating system: Linux 2.6.30-gentoo-r2
PHP version: 5.3.1
PHP Bug Type: PDO related
Bug description: PDO DBLIB Fails with OOM
Description:
------------
When querying large tables (> 800,000 rows) with PDO DBLIB I get out of
memory.
The same select query works fine using:
linux# tsql -H host -U user -P pass
SELECT * from aVeryLargeTable
go
quit
on the command line using the freetds (dblib) library without consuming
client-side memory.
Reproduce code:
---------------
$pdo = new PDO('dblib:host=host','user','pass');
echo "Creating table...\n";
$pdo->query("CREATE TABLE large_table (field_1 nvarchar(4000))");
$pdo->query("DECLARE @n int;
set @n = 0;
WHILE (@n < 50000) BEGIN
insert into large_table values( replicate(4000,'-') );
set @n = @n + 1;
END");
echo "Prepare\n";
$rs = $pdo->prepare("SELECT * FROM large_table");
echo "Execute\n";
/*********OOM HERE**************/
$rs->execute( );
Expected result:
----------------
A valid handle to a resultset in $rs
Actual result:
--------------
Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to
allocate 48 bytes) in /home/ssufficool/tds_test.php on line 12
It looks like the guts of
ext/pdo_dblib/dblib_stmt.c:pdo_dblib_stmt_execute()
at "/* let's fetch all the data */"
Should be moved to:
pdo_dblib_stmt_fetch()
and only when a scrollable cursor is requested should the data be buffered
at the client (not required for ct-lib)
--
Edit bug report at http://bugs.php.net/?id=50755&edit=1
--
Try a snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=50755&r=trysnapshot52
Try a snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=50755&r=trysnapshot53
Try a snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=50755&r=trysnapshot60
Fixed in SVN:
http://bugs.php.net/fix.php?id=50755&r=fixed
Fixed in SVN and need be documented:
http://bugs.php.net/fix.php?id=50755&r=needdocs
Fixed in release:
http://bugs.php.net/fix.php?id=50755&r=alreadyfixed
Need backtrace:
http://bugs.php.net/fix.php?id=50755&r=needtrace
Need Reproduce Script:
http://bugs.php.net/fix.php?id=50755&r=needscript
Try newer version:
http://bugs.php.net/fix.php?id=50755&r=oldversion
Not developer issue:
http://bugs.php.net/fix.php?id=50755&r=support
Expected behavior:
http://bugs.php.net/fix.php?id=50755&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=50755&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=50755&r=submittedtwice
register_globals:
http://bugs.php.net/fix.php?id=50755&r=globals
PHP 4 support discontinued: http://bugs.php.net/fix.php?id=50755&r=php4
Daylight Savings: http://bugs.php.net/fix.php?id=50755&r=dst
IIS Stability:
http://bugs.php.net/fix.php?id=50755&r=isapi
Install GNU Sed:
http://bugs.php.net/fix.php?id=50755&r=gnused
Floating point limitations:
http://bugs.php.net/fix.php?id=50755&r=float
No Zend Extensions:
http://bugs.php.net/fix.php?id=50755&r=nozend
MySQL Configuration Error:
http://bugs.php.net/fix.php?id=50755&r=mysqlcfg
