如何计算 mysql 中的总行数而不会出现致命错误：允许 memory

Question

I got a problem Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 141954624 bytes) when to count all of row mysql table

$query = $db->query("SELECT * FROM table");
$count = $db->num_rows($query);

echo $count;

Total rows about 17k and I got Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 141954624 bytes) . Let me know, how to fix it.

Answer 1

You could change your SQL query to...

SELECT COUNT(*) AS `rows_count` FROM `table`;

Then you don't have to load such a large recordset to just then use a row counting function to get the number of rows.