SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37507a32fadf6d2165ccda070e922841922c1140c3d3dc721f2145c57297fcda' 
  AND token = 'kLH6hHzQhBqR0FoPA8qDupOg9mZf2iiwKrzGmoVVYDY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}