SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '066f6c7c4781206776318d027d64bd8caa08b50342d532e222bfd35112545b24' 
  AND token = 'Zkv2NqyKeTO7YOhUl4ejkLQfQkPrEGVGvDOgZmFsU6U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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