Datatypes design and implementation choices are not to be taken lightly. These are the foundations upon which your databases will be built, and they will reflect on all database users and applications.

I spent a lot of space discussing DATETIME datatypes because these involve a lot of complexity and are commonly used.

XML and CLR also received substantial coverage. There are three reasons for this: they are new to SQL Server 2005, they have great potential for enhancing the productivity of your database, and they have great potential for misuse and abuse. I hope you were convinced that CLR and XML fit well in the relational model if you use them wisely. That’s the key–using them wisely. Education will play a vital role in determining whether XML and CLR support will ultimately succeed or fail.