Искам като някой напише http://saita.net/read_more.php?page=obqvi&id=100 например и ако няма таъв запис в таблицата да не искарва съобщение за грешка като това:
CODE

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Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 84 Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 86 Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 88 Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 94 Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 96 Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 98 Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 100 Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 102 Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 104 Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 106 Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 108 Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 110 Warning: mysql_result() [function.mysql-result]: Unable to jump to row 0 on MySQL result index 4 in /home/skarabeq/public_html/obqvi/read_more_pod_naem_office.php on line 112

А да искарва празна страница или някакво съобщение, че страницата която се опитва да намери не съществува.Как може да стане това ?

Ми чрез mysql_num_rows или count(pole) преброяваш колко намерени резултата има от обяви с id 100 то предполагам id са уникални това значи, че ще са 0 или 1 запис.
проверяваш ако е 0 да му изкара грешка, че няма такъв запис, но ако са повече от 0 си продължаваш с кода :)

Можеш ли да ми дадеш пример с код ?

$query = mysql_query("SELECT * FROM lyric WHERE id = '$id' LIMIT 1");
if(mysql_num_rows($query)){
while($row = mysql_fetch_array($query)){
echo "asdasda";
}
}
else echo "nqma takava alalalalaal";