#36144 [Opn->Asn]: only one row when using persistent connections and unbuffered queries
ID: 36144
Updated by: sniper@php.net
Reported By: php at kanariepiet dot com
-Status: Open
+Status: Assigned
Bug Type: MySQL related
Operating System: Linux
PHP Version: 5.1.2
-Assigned To:
+Assigned To: andrey
New Comment:
Assigned to the MySQL support.
Previous Comments:
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[2006-01-24 15:30:13] php at kanariepiet dot com
Description:
------------
Assume you have a webserver serving two PHP scripts. Both PHP
scripts use persistent MySQL database connections. Script one
uses normal mysql_query calls, script two uses
mysql_unbuffered_query calls.
Also, script one is doing additional mysql_query calls while
retrieving the records of the first mysql_query (yes, an sql
join would be better).
When script two (the one with mysql_unbuffered_query)
finishes, and script one reuses the persistent database
connection of script two, the resource identifier in script
one gets lost after the first loop, resulting in only one
returned row.
get_resource_type($res) should return 'mysql result', but will
return 'Unknown'
Reproduce code:
---------------
Script1.html:
$db = mysql_pconnect ('host', 'user', 'pass');
print ('We are using MySQL thread: '. mysql_thread_id() .'<br />');
$res = mysql_query ("SELECT * FROM temp.documents"); // table with
1200 records
print ('mysql_num_rows() returned '. mysql_num_rows($res) .'<br />');
while ($row = mysql_fetch_assoc ($res)) {
$res2 = mysql_query ("SELECT * FROM temp.attachments WHERE document =
". $row['id']);
while ($row2 = mysql_fetch_assoc ($res2))
$row['attachments'][] = $row2;
$documents[] = $row;
}
print ('number of documents: '. count ($documents));
Script2.html:
$db = mysql_pconnect ('host', 'user', 'pass');
print ('We are using MySQL thread: '. mysql_thread_id() .'<br />');
$res = mysql_unbuffered_query ("SELECT * FROM temp.documents");
while ($row = mysql_fetch_assoc ($res)) {
}
Expected result:
----------------
Open script2.html and note the thread id.
Keep opening script1.html until the thread id is the same as
the one script2 used.
You should see this:
(script2.html)
We are using MySQL thread: 1439
(script1.html)
We are using MySQL thread: 1439
mysql_num_rows() returned 1200
number of documents: 1200
Actual result:
--------------
However, the output will be:
(script2.html)
We are using MySQL thread: 1439
(script1.html)
We are using MySQL thread: 1439
mysql_num_rows() returned 1200
number of documents: 1
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