SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0d04033ccc5ce2b456298c6157ecd5b7cab344ddbd052d570868e12b3e70c64' 
  AND token = 'H2LGTIfaaQpfq3Mry/OBdOuShMrtalXaENCksXkA7v4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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