SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c48653b9c05a0e5e8df25b1b67c15c733c4b1c1ecbc6ccc2bcc77caa4cd7089' 
  AND token = 'Z8uDrDnXPUgDxKWbw96zNj8h6SjAc6pZKK2ylyWeC1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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