SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cbbf18a00f5d2f8f7b32417ad11d70f9d1edd9259e120821889fd3c709e273bf' 
  AND token = 'iKaBsZoMEMxuIktSvnuxFbvIw8Zwde1hOlCgkhmiiug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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