Editions - MS SQL
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MS SQL Databases
What Version of MS SQL should be used?
MS SQL Express can be used in most cases. However, there are a couple of limits to be aware of related to the Express edition.
The Express edition can handle databases up to 4 GB in size. If you need a database larger than 4 GB you will need the Web Edition of MS SQL Server.
The Express edition can only utilize up to 1 GB Ram. If you have a busy database or will have several databases with normal traffic, you will notice a performance improvement with more than 1 GB Ram, in which case you would want the Web Edition.