msql_num_rows()

(PHP 4, PHP 5, PHP 7)

Get number of rows in result

说明

msql_num_rows(resource $query_identifier): int

msql_num_rows() returns the number of rows in a result set.

参数

$result: resource型的结果集。此结果集来自对msql_query()的调用。

返回值

Returns the number of rows in the result set.

参见

msql_num_fields()Get number of fields in result

If you would like to just find out how many rows are returned by a query without actually using the results, then it's much more efficient to use SQL count function (specially for large tables with millions of rows).
<?php
$sql = "SELECT COUNT(indexed-field) AS cnt FROM some-table";
$r = mysql_query($sql);
$row = mysql_fetch_object($r);
echo $row->cnt;
?>