SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'adbdedc57edbfd0183bd2685d552586525fcce5aba1affd1d92de21795f8106e' 
  AND token = 'GrkDdKo0KynEpxXU8rEGxvU5/49FQDGtpKP4d3PSPfs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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