用特殊的“关键字”（SQL）计算表行

Question

I have a SQL-table called "usermeta" , inside this table are lots of columns and rows. I need the column "meta_key" and want to count the rows with the keyword "Users" .

Whats wrong with my script?

<?php
$user_count = $wpdb->get_var( "SELECT COUNT(meta_key) AS Users FROM $wpdb->usermeta" );
echo "<p>Users count: {$user_count}</p>";
?>

Answer 1

SQL query should be

SELECT COUNT(DISTINCT meta_key) FROM  usermeta WHERE meta_key LIKE '%Users%'

and since we did not want unique results

I always get "1" - does it only counts this entry once? – Pepe

and code should be therefore

<?php
$user_count = $wpdb->get_var( "SELECT COUNT(meta_key) AS Users FROM $wpdb->usermeta WHERE meta_key like '%Users%'" );
echo "<p>Users count: {$user_count}</p>";
?>

Answer 2

You should probably use a WHERE clause to filter for rows with have your keyword. For a detailed answer you should explain more one how your table actually looks like.