Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '21a6781f7e70dedc87f8f0dd8d0ad2968fc68e42afe956b997294c100d01dcb2' 
  AND token = '+xFobP3PMqxasTckHmySmqCx07B1yE9peTp7M4jixRk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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