SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '879968b053e221188c5acd81db56efa91d000b442308e9d9662437b3063f03a4' 
  AND token = 'p5WygoGMlXYvN8MOwoC0jUWx8XBQ3eDicthOlKHuKps=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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