SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de4c398722efe2e3619146f95429f22f99a6185fa77655e0fa713bfe55c34b31' 
  AND token = 'Z701HpA/dRKyEUndDMPS2TuwZWD3helx4GTJynOVpaU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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