Filters through relations

[snit-ram]

Adding support for filtering data through relationships. Good examples of this can be found in the file test/associations/multiple-level-filters.test.js

Here is the added behavior:

Task.findAll({
  where: {
    'project.user.username': 'leia'
  }
}).success(function(tasks){
  //...
});

By running this code, it sequelize will interpret the where clauses adding all the necessary joins to able to run the filter.

Hope you guys like it and consider the merging

[sdepold]

wow. need to take some further time to review the code :)

[snit-ram]

I know i'ts big and can seem scary at the first look, but let me give you guys an overview.

• Theres a lot of new functions to identify this type of filtering and to get the necessary joins
• hashToWhereConditions, getWhereConditions and selectQuery are the mysql version with minor changes to support the new filtering.
• I've extracted some database-specific code (like boolean value serialization, select from an array in postgres, and limit & offset) to smaller functions. Due to this change, hashToWhereConditions, getWhereConditions and selectQuery are now the same for every database and was moved to the abstract query generator. That's why you guys see a lot of deletions.

That's it. I tried to follow your code style, so it should not be that difficult to read.

The tests also help to understand the purpose of the change, and are passing in all databases.

If you guys need something from me in order to merge it, please tell me. I'll be glad to help.

[sdepold]

pretty awesome stuff :)