[From SQL Server Central
I have a love hate affair with user defined types. I was first exposed to their benefits when I went on the original Microsoft SQL 6.5 database design course. My first reaction was "WOW, this is a really cool idea" but now I am much more circumspect in how I use them.
Their advantages are immediately apparent
- They greatly simplify the creation of the database schema
- They aid in standardization across the schema.
When I was first learning about UDTs their disadvantages were not discussed and it was only through trial and error that their limitations became apparent.
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