src/Db/Db.php
public function indexCompare(array $a, array $b) {
        if ($a['columns'] > $b['columns']) {
            return 1;
        } elseif ($a['columns'] < $b['columns']) {
            return -1;
        }

        return strcmp(val('type', $a, ''), val('type', $b, ''));
    }
public function indexCompare(array $a, array $b) {
        if ($a['columns'] > $b['columns']) {
            return 1;
        } elseif ($a['columns'] < $b['columns']) {
            return -1;
        }

        return strcmp(val('type', $a, ''), val('type', $b, ''));
    }
Compare two index definitions to see if they have the same columns and same type.

@param array $a The first index.
@param array $b The second index.
@return int Returns an integer less than, equal to, or greater than zero if {@link $a} is
considered to be respectively less than, equal to, or greater than {@link $b}.