This is the overview page of the Exam. I strongly suggest going over the Skills Measured section. Ensure you have a good understanding of them. Including all the different options for Triggers, XML, Indexed Views etc.
Exam 70-461 Querying Microsoft SQL Server 2012
The Training Kit book is a great reference resource. In the front it highlights the skills measured and which chapters focus on those. One word of warning, the practice test that comes with the book is far easier than the actual exam. Use it as a guide on how the questions will be asked.
Amazon - Training-Kit-Exam-70-461-Microsoft
Microsoft 70-461 Test Preparation - This is a playlist of 10 videos which will give you a good overview. The videos dont cover everything but its a great start. I suggest even if you are not planning on taking the Exam its a good set of videos to watch to improve your knowledge.
Playlist of 10 Videos on You Tube
MCSA Certification Prep | Exam 461: Querying Microsoft SQL Server 2012 - This is from Microsoft to give you an overview and tips on what to study on
Microsoft Exam Preperation Guide
What's New in SQL Server 2012 (Part 2 of 13) - New Transact-SQL Enhancements - New Features of SQL 2012 which will of course be asked about during the exam
New Features of SQL 2012 - Querying
The Microsoft Virtual Academy has some good videos as well.
Querying Microsoft SQL Server 2012 Databases Jump Start