Row count with PDO

Question

There are many conflicting statements around. What is the best way to get the row count using PDO in PHP? Before using PDO, I just simply used mysql_num_rows.

Answer 1

As I wrote previously in an answer to a similar question, the only reason mysql_num_rows() worked is because it was internally fetching all the rows to give you that information, even if it didn't seem like it to you.

So in PDO, your options are:

1. Use PDO's fetchAll() function to fetch all the rows into an array, then use count() on it.
2. Do an extra query to SELECT COUNT(*), as karim79 suggested.
3. Use MySQL's FOUND_ROWS() function UNLESS the query had SQL_CALC_FOUND_ROWS or a LIMIT clause (in which case the number of rows that were returned by the query and the number returned by FOUND_ROWS() may differ). However, this function is deprecated and will be removed in the future.