how to convert sql query into mongodb code example

Example: sql to mongodb query converter

The simple anwser? No.

The slightly more complex anwser is some people have had luck translating more complex SQL to Mapreduce functions ...

http://rickosborne.org/blog/index.php/2010/02/08/playing-around-with-mongodb-and-mapreduce-functions/

http://rickosborne.org/blog/index.php/2010/02/19/yes-virginia-thats-automated-sql-to-mongodb-mapreduce/

However, that said ... generally speaking you might as well learn mapreduce properly because if the data is in MongoDB already ... you'll really need to know how to properly query MongoDB to get anything meaningful done!

MongoDB has wonderful and helpful docs http://www.mongodb.org/display/DOCS/Advanced+Queries

As well as an easy to use online tutorial: http://try.mongodb.org/