SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ab0461fcea786739b30c6354d1968a3863bf7089342a878e253c05332eeab87' 
  AND token = '6BJCVuV7YKhYQcA2kxEDruHUsIWNaA5+T46aHAiUXCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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