How to delay INSERT time?

I'm using simplepie. I want to store the rss feeds items into mysql database.
I've been parsing every RSS items into $link,$title,$date,$content.
But simplepie get the rss feeds from its resource need few seconds and insert into just one moment, that cause it always stores first few lows of RSS items, not all of them.
How to delay INSERT time that can store all of the rss items into mysql database?TXS