SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9bd260bd7ca7b0e30f0f5067ee01f87f10eda0166b74d70784921a5111d55c7' 
  AND token = 'vV41/bhOy3UsVsTUurUNZvykr0arBCpNMLvvlkvIrw4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00087

JSON explain

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