#40869 [Opn->Fbk]: Mysql gives incorrect result, using subqueries and variables

ID: 40869 Updated by: tony2001@php.net Reported By: robert dot allen at unearthtravel dot com -Status: Open +Status: Feedback Bug Type: MySQL related PHP Version: 5.2.1 New Comment: Which OS is that? Previous Comments: ------------------------------------------------------------------------ [2007-03-20 18:07:52] robert dot allen at unearthtravel dot com To be honest I am not sure how to do this, I have tried it on an xampp bundle though and so presume they would have linked them correctly. I have also tried on our hosted managed server and get the same result in both places. Thanks for your help Rob ------------------------------------------------------------------------ [2007-03-20 17:45:35] tony2001@php.net Make sure PHP is linked with the correct libmysql, it should be of the same version as the server. ------------------------------------------------------------------------ [2007-03-20 17:40:43] robert dot allen at unearthtravel dot com Description: ------------ Hi We are getting an odd result when submitting a query to a mysql server (4.1.10), we get a different result when performing the query through php (an incorrect result) as opposed to straight in to a mysql client. It seems to have performed the sub-query twice, so the variable @j has been incremented twice. A simplified version of our code is shown below and reproduces the problem, I have also included a sample table. I have seen it on both windows and linux. Reproduce code: --------------- mysql_query("SET @j=0;"); $sql = "select offset from (select @j:=@j+1 as offset, if(element_id=2,1,0) as result from element) as t1 WHERE t1.result=1 "; $result = mysql_query($sql); $row = mysql_fetch_row($result); echo $row[0]; /******************DATABASE****************/ CREATE TABLE element ( element_id int(10) unsigned NOT NULL auto_increment, element_type_id int(10) unsigned NOT NULL default '0', lock_level int(10) unsigned NOT NULL default '0', PRIMARY KEY (element_id), KEY new_index (element_type_id) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci; /*Data for the table element */ insert into element(element_id,element_type_id,lock_level) values (1,1,0); insert into element(element_id,element_type_id,lock_level) values (2,10,0); insert into element(element_id,element_type_id,lock_level) values (3,2,0); insert into element(element_id,element_type_id,lock_level) values (4,10,1); insert into element(element_id,element_type_id,lock_level) values (5,2,0); Expected result: ---------------- 2 Actual result: -------------- 7 ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=40869&edit=1