Design of database and Itemhistory element

I have entity 'Article' and it has the attribute 'Price' and the change of price-s and must be counted as the price history. What the database design would be appropriate?

TABLE Item (ID, Price);
TABLE ItemPriceHistory (ItemID, Price, Date)

or

other way?
If the element is first inserted into the system, then ItemPriceHistory remains empty after the first change of this element on the column "Item.Price" we would insert record with old price in the ItemPriceHistory table.

Thank you.

CharlesRoos wrote:
>
Distribute the data in two tables goes against good design.
>
I do not SHARE, I duplicate.

Even worse!

I save current/actual price in the history table and in the main table, and I do it for performance reasons.

What about using partitioned tables? Performance should not be a problem.

Duplications and aggregations are part of the modern design of the database. See table of header lines / mentioned above, modern database systems have "Header.TotalSum = SUM (Line.Price)", so it does not accelerate get the sum total of header lines. This aggregation is not just a "good design"? Well good or not, it is widely used in modern solutions.

No, storage of aggregations is part of the data warehouse design, design of non-relational databases. Duplication is hardly necessary in any design of the database.

Published by: BluShadow on Sep 15, 2010 09:28
correct terminology

Tags: Database

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