Hello All,
When creating my database I have modeled some of the tables after the Adventureworks sample database.
There are some fields or entire tables in Adventureworks that I do not see an imediate use for, however; I would hate to ommit them to find out later they would have been benificial. (.eg territory table).
In general terms what would the impact be on size and performance of a database which contains tables or fields that do not contain data.
Thanks for your help!
Blair:
There will be little impact from tables that are not used provided these tables are small and do not grow. If the tables are large then they can impact your storage requirements and the size and speed of your backups.
Fields that are not used are a different story -- especially if the fields are populated with large amounts of "spectator" data. These "spectator" fields will then impact the amount of space required for their tables and will have an impact on the amount of time required for a "table scan". This becomes amplified to some extent if these fields participate in any indexes. If your fields are all null the amount of bloating will not be as great.
Another problem that can occur if you leave in fields that have at the moment no use is that in the future it can become tempting for somebody to start "using" these fields in ways that are not planned. Eliminating unused fields can stop this kind of "cobbling" before it takes place.
I would suggest that you are better off with a well designed, well thought out database in which each column has a specific meaning with a specific intended use.
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