SQL error Warning: mysql_result() Unable to jump to row 0 on MySQL

I have this error message in a site

Code:

Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 52 in /www/php/php_files/details.php on line 23

This is line 23

Code:

AND m.main_nr = "'.mysql_result($result, 0, 'm.main_nr').'"

I have test it run with a backup of sql files, and have the error. on Mai was no problem in this site, i have server not cahnge only updates do of mysql5 and php5.

The complete area of this line of 23 is

Code:

 $sql = 'SELECT z.name
                FROM sys_main m, sys_link l, sys_zusatz z, sys_kat k
                WHERE m.main_nr = l.main_nr
                AND l.zusatz_nr = z.zusatz_nr
                AND z.kat_nr = k.kat_nr
                AND m.main_nr = "'.mysql_result($result, 0, 'm.main_nr').'"
                AND k.name = "Modell"';
        $resultmodell = mysql_query($sql);

PHP Error Messages compl.

Code:

#	Time	Memory	Function	Location
1	0.0013	130944	{main}( )	../index.php:0
2	0.1063	5210940	require_once( '/www/php/components/com_content/content.php' )	../index.php:236
3	0.1159	5715824	JCache_Lite_Function->call( )	../content.php:53
4	0.1160	5715824	call_user_func_array ( )	../joomla.cache.php:58
5	0.1160	5715824	Cache_Lite_Function->call( )	../joomla.cache.php:0
6	0.1161	5759504	call_user_func_array ( )	../Function.php:100
7	0.1161	5760024	showItem( )	../Function.php:0
8	0.1304	5797676	show( )	../content.php:1531
9	0.1314	5797956	JCache_Lite_Function->call( )	../content.php:1731
10	0.1314	5797956	call_user_func_array ( )	../joomla.cache.php:58
11	0.1314	5797956	Cache_Lite_Function->call( )	../joomla.cache.php:0
12	0.1315	5842320	call_user_func_array ( )	../Function.php:92
13	0.1315	5842364	HTML_content::show( )	../Function.php:0
14	0.1396	6130720	mosMambotHandler->trigger( )	../content.html.php:461
15	0.1397	6131596	call_user_func_array ( )	../joomla.php:4350
16	0.1397	6131656	botAddPhp( )	../joomla.php:0
17	0.1406	6222688	include( '/www/php/php_files/details.php' )	../rd_addphp.php:56
18	0.1410	6223680	mysql_result ( )	../details.php:32

 

I guess that something's wrong with the part in red:

AND m.main_nr = "'.mysql_result($result, 0, 'm.main_nr').'"

Maybe an empty result?

 

Thanks Falco

is m.main_nr a table

 

The table is called m, and m.main_nr refers to the column main_nr in the table m.