Edit report at http://bugs.php.net/bug.php?id=54444&edit=1
ID: 54444
Updated by: u...@php.net
Reported by: peter dot colclough at toolstation dot com
Summary: Multiple Queries on a single conenction
Status: Bogus
Type: Bug
Package: MySQLi related
Operating System: Ubuntu 10 64 bit
PHP Version: 5.3SVN-2011-04-01 (SVN)
Block user comment: N
Private report: N
New Comment:
Hmm, you can prepare as many statements as you want per connection. But
once you have executed a statement on a connection you must fetch its
results before you can execute another statement. The result set
"blocks" the line.
You can, of course, do an implicit fetch on the C level upon execute but
that's the exact opposite of the default fetch method (unbuffered) used
for prepared statements by MySQL.
Its a one-liner to do that fetch in user land. No need for changes on
the C level.
$mysqli = new mysqli("localhost", "root", "root", "test");
$stmt1 = $mysqli->prepare("SELECT 1 AS _one FROM DUAL");
$stmt2 = $mysqli->prepare("SELECT 2 AS _two FROM DUAL");
/* execute */
if (!$stmt1->execute())
printf("[001] [%d] %s\n", $stmt1->errno, $stmt1->error);
/* clear line by fetching result set */
$res1 = $stmt1->get_result();
/* execute */
if (!$stmt2->execute())
printf("[002] [%d] %s\n", $stmt2->errno, $stmt2->error);
/* clear line by fetching result set */
$res2 = $stmt2->get_result();
/* fetching second first */
while ($row = $res2->fetch_assoc())
var_dump($row);
$res2->free();
while ($row = $res1->fetch_assoc())
var_dump($row);
$res1->free();
Previous Comments:
------------------------------------------------------------------------
[2011-05-09 16:35:37] peter dot colclough at toolstation dot com
Thanks for teh feedback. I was also getting that error, just wanted to
make sure it wasn't 'me'... but actually expected behaviour.
Am now devbeloping my own, that allows multiple statements per
connection, as well as multiple 'prepare' statements. This will be open
sourced when ready.
The current mysqli interface should have been able to do this, but it
was obviously decided not to allow it... which is a bit of a pain.
Thanks again for your input
------------------------------------------------------------------------
[2011-05-09 16:14:45] u...@php.net
You can answer this question yourself by adding a bit of error handling
to your script such as ...
$mysqli = new mysqli("localhost", "root", "root", "test");
$stmt1 = $mysqli->prepare("SELECT 1 AS _one FROM DUAL");
$stmt2 = $mysqli->prepare("SELECT 2 AS _two FROM DUAL");
if (!$stmt1->execute() || !($meta1 = $stmt2->result_metadata()))
printf("[001] [%d] %s\n", $stmt1->errno, $stmt1->error);
if (!$stmt2->execute() || !($meta2 = $stmt2->result_metadata()))
printf("[002] [%d] %s\n", $stmt2->errno, $stmt2->error);
... and the answer is:
[002] [2014] Commands out of sync; you can't run this command now
------------------------------------------------------------------------
[2011-04-01 16:13:48] peter dot colclough at toolstation dot com
Description:
------------
Hi, trying to build a generic DB object handler for mySqli, and have hit
an issue where we can't have more than one open query on the same
connection. Is this a bug or 'expected behaviour'?
Looking at the mysqli.c source code, it looks like it should have been
possible, but it looks like the second object overwrites the first...
I have put a sample snippet below of what I am trying to achieve.... if
this helps.
Any help greatly appreciated....
OS: 2.6.32-21-generic #32-Ubuntu SMP Fri Apr 16 08:09:38 UTC 2010 x86_64
GNU/Linux
PHP Version => 5.3.2-1ubuntu4.5
Test script:
---------------
-------------- Code Snippet -----------------------------
$sqlstock = 'select foo1 from bar1 where foo1 =?';
$sqltime = 'select foo2, foo3 from bar2 where foo4 =?';
$varinp = "XXXXXXXXXXXX";
$abindVars = array(0=>$varinp);
$varProd = '';
$conn = dbi->db_conn;
$sprod = '';
$timestart = microtime_float();
// Get a statement
$aRes = array();
$aRes2 = array();
// Init 2 Statements
$stmt = mysqli_stmt_init($conn);
$stmt2 = mysqli_stmt_init($conn);
// Prepare 2 statements
mysqli_stmt_prepare($stmt,$sqlstock);
mysqli_stmt_prepare($stmt2,$sqltime);
// Set the bind variable
$varinp = "PXX00019263";
// Bind the statements
mysqli_stmt_bind_param($stmt,'s', &$varinp);
mysqli_stmt_bind_param($stmt2,'s', &$varinp);
// Execute - Second one fails
mysqli_stmt_execute($stmt);
mysqli_stmt_execute($stmt2);
// Set up field Defs
$aFieldDefs = array();
$aFieldDefs2 = array();
// Get result Metadata
$result = mysqli_stmt_result_metadata($stmt);
$result2 = mysqli_stmt_result_metadata($stmt2);
$nCount = 0;
while($aFieldDefs[$nCount] = mysqli_fetch_field($result)){
echo('Field = '.print_r($aFieldDefs, true)."\r\n");
$aRes[$aFieldDefs[$nCount++]->name] = null;
}
$nCount = 0;
while($aFieldDefs2[$nCount] = mysqli_fetch_field($result2)){
echo('Field = '.print_r($aFieldDefs2, true)."\r\n");
$aRes2[$aFieldDefs2[$nCount++]->name] = null;
}
// Bind Results
mysqli_stmt_bind_result($stmt, &$aRes['foo1']);
mysqli_stmt_bind_result($stmt2, &$aRes2['foo2'], &$aRes2['foo3'])
// Fetch Results
mysqli_stmt_fetch($stmt);
mysqli_stmt_fetch($stmt2);
echo(print_r($aRes, true)."\r\n");
echo(print_r($aRes2, true)."\r\n");
--------------- End Code Snippet ----------------------
Expected result:
----------------
Array
(
[foo1] => 'PXX00019263'
)
Array
(
[foo2] => 2009-09-15 12:05:02
[foo3] => 0000-00-00 00:00:00
)
Actual result:
--------------
Array
(
[foo1] =>
)
Array
(
[foo2] => 2009-09-15 12:05:02
[foo3] => 0000-00-00 00:00:00
)
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/bug.php?id=54444&edit=1
