SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc056803acb2a507812052cffbc190c39728fa4e0475bb8d467797692571def1' 
  AND token = 'xGICKf68iG02vJGh5YdWCL9+jsyNpX87Aa5c57arLSQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}