Помогите связать разные условия выборки запроса sql php

$sql = "SELECT rg.federal_district,cty.city, p.surname, p.name, p.middlename, p.email, p.phone, a.* FROM {$table} AS a JOIN profiles AS p ON p.id = a.profile_id LEFT JOIN city AS cty ON cty.id = p.city LEFT JOIN districts AS rg ON rg.id = p.region ";

$where .= ($first) ? " WHERE {$key} LIKE '%{$_GET[$key]}%' " : " AND {$key} LIKE '%{$_GET[$key]}%' ";

и связать

$total_pages_sql = "SELECT COUNT(*) FROM {$table} {$where}";

и сюда

$sql .= $where;

$sql .= "LIMIT {$offset}, {$no_of_records_per_page}";

есть какая-то функция ?