After a bit of work it is now possible to use sql to parse json using javascript!. I introduce to you version 0.1 of JsonSQL. Given a javascript object you can write a simple select statement to filter, order and limit the object:

jsonsql.query("select title,url from json.channel.items
where (category=='javascript' || category=='vista')
order by title,category asc limit 3",json);

Give it a shot. It would be nice to expand this a little more with a few aggregate functions (distinct, count, etc..).