ID: 21806
Updated by: [EMAIL PROTECTED]
Reported By: mayc at imsweb dot com
-Status: Open
+Status: Closed
Bug Type: Sybase-ct (ctlib) related
Operating System: Solaris 7
PHP Version: 4.3.0
New Comment:
docs are updated.
Previous Comments:
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[2003-03-25 17:32:36] [EMAIL PROTECTED]
Use the parameter store_result of sybase_unbuffered_query to
prevent it from "eating" memory.
sybase_unbuffered_query(string query [, int link_identifier [, bool
store_result]])
>From documentation (which is not online yet):
The optional <parameter>store_result</parameter> can be FALSE to
indicate
the resultsets should'nt be fetched into memory, thus minimizing
memory usage
which is particularily interesting with very large resultsets.
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[2003-01-21 14:58:15] mayc at imsweb dot com
Large selection sets using sybase_query use too much memory, since it
pulls the entire result set into memory. In my example, the memory of
the httpd daemon quickly builds to about 155MB before the 30 second
timeout. I had figured that sybase_unbuffered_query would solved that
problem. Unfortunately, it also bleeds memory, however not as bad. It
raises the memory usage of the httpd daemon to 53MB before the 30
second timeout.
I believe this is either a memory leak, or unbuffered query is actually
still buffering something.
Below is a simplified example that shows the memory leak. I am using
Solaris 7, Sybase 11.9.2, and PHP 4.3.0.
Chuck
---------------------------
sybase_min_server_severity(11);
$con = sybase_connect('peach5026d', 'may', '********');
sybase_select_db('db_dev', $con);
$fp = fopen('test.csv', "w"); // open the output file
$query = sybase_unbuffered_query("SELECT * FROM vial v WHERE v.study_id
= 'ACC'", $con);
$max = sybase_num_fields($query);
while($row = sybase_fetch_row($query)) {
$elements = array();
for ($j = 0; $j < $max; $j++)
$elements[] = $row[$j];
fwrite($fp, implode(',', $elements) . "\r\n");
}
@sybase_free_result($query);
fclose($fp); // close the file
@sybase_close($con);
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Edit this bug report at http://bugs.php.net/?id=21806&edit=1
