Winamp & Shoutcast Forums - PHP/SQL Question.

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PHP.net
It is faster to run second query "select count(...) from ... ", than adding SQL_CALC_FOUND_ROWS to your first query, and then using select FOUND_ROWS() + mysql_num_rows().

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PHP.net
The reason it's just as slow is that to count that way as it is to fetch, minus the data transfer.

Even when executing a limit query, when you ask it to fetch the number of total rows, it must scan the whole table every time to calculate the count.

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PHP.net
The fastest way to get the number of rows in a table is doing this:

$total = mysql_result(mysql_query("SELECT COUNT(id) FROM yourtable"),0);

As long as there are no NULL ids (shouldnt be), it will return the correct rows extremely fast. If you already used yourtable though, it is faster to use mysql_num_rows() on the result of it.