Great, now miss out the SQL
That's great, now you can make it faster by not putting the data in the SQL database in the first place...saving the query optimization to get it out again and shoving it into your mapreduce directly.
As Jeremy recently discovered:
http://jeremy.zawodny.com/blog/archives/010523.html
Remember folks, SQL databases are for data that can be
1. Run against a query that can be expressed in SQL syntax
2. That query can be improved by one or more indexes
3. The burden of making the index is less than the time it saves in your queries.
If it can't be expressed in SQL then the query can't be reduced and you end up reducing the data instead..... which is the point of map-reduce.
Test: Given a changing set of points in 3d, run a query against a snapshot of that data that returns the nearest point to (x,y,x)... feel free to express that in sql....