SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '193c5f329198adf347d1502c8fe8512c00436fdb92ac8affed77f98a1e62281e' 
  AND token = 'd9aKqTV8z+tvZoWZtFt9xcvXu5XFBR4V556qiVENBJw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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