SQL 2008 and later? There's a date data type now that just stores mm/dd/yyyy at less than half the size of datetime. Need to store just mm/dd/yyyy? Prior to SQL 2008, the smalldatetime data type was appropriate. Starting with SQL 2008, there is no good reason to use the datetime data type. It might be an old habit, but Datetime just isn't needed any more, there are far superior options out there for every use. Here's my five scariest SQL Server data types, ordered by degree of fright ascending:ĥ. Datetime – This one has not only been unnecessary for many years, with smalldatetime a better choice in many cases, it's been replaced recently by the superior DateTime2 and Date data types. Making these choices right from the start is the best way to prevent a performance - or data quality - scare down the line. At scale, poor data type changes can limit performance in a very noticeable way, and reversing these poor decisions down the line is time-consuming and requires an outage. Poor data type choices have significant impact on storage, not just on disk, but in backups and in memory. These decisions are much more than a 'what's new' or personal preference.

‘Tis the season for 'scary' things, so in the spirit of the fun, I present the five scariest data types to see in the design of your SQL Server tables.

Sql server data types