• Hibernate, nHibernate, Entity Framework and Lynq are just a few of the Object Relational Mapping tools you're going to see more of. They actually can work very well for most queries (around 95-98%). However, there are things to watch for. First, make sure they're using the appropriate data lengths in their prepared statements. You'll frequently see VARCHAR(3) for 'Dog' and VARCHAR(5) for 'Horse' when the column is actually VARCHAR(50). This results in a bunch of execution plans that are compiled but not reused. Also watch for the N+1 problem. It's very common. There are other issues you might hit from these tools as well. Just work with the Devs on addressing them. Trying to stop the use of these tools is a fools errand. Go in with a "let me help this all work better" attitude.

    "The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
    - Theodore Roosevelt

    Author of:
    SQL Server Execution Plans
    SQL Server Query Performance Tuning