SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '365767b8a3b2c8c83b140f82314ed564331b70673e26bfeefc9af3dec84c43e6' 
  AND token = 'rH9I6uQb/Rxj6B7SodUPDMDuScMHOP5QDWS3iA/i0yY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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