CODEWITHSUNDEEP
mysqlruby-on-railsruby-on-rails-3mongodbmongoid
user1438327
user1438327

Reputation:

MySQL to MongoDB conversion

How do I convert the following into MongoDB query ?

sets_progress = Photo.select('count(status) as count, status, photoset_id')
                     .where('photoset_id IN (?)', sets_tracked_array)
                     .group('photoset_id, status')

Upvotes: 0

Views: 192

Answers (1)

Jesse Wolgamott
Jesse Wolgamott

Reputation: 40277

There is no 1 to 1 mapping of a SQL query to a NoSQL implementation. You'll need to precalculate your data to match the way you want to access that data.

If it is small enough, then this query will need to change into a map-reduce job. More here: http://www.mongodb.org/display/DOCS/MapReduce

Here's a decent tutorial that takes a query that GROUP's and converts to map-reduce: http://www.mongovue.com/2010/11/03/yet-another-mongodb-map-reduce-tutorial/

Upvotes: 1

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