Question

I’m developing a database and need to know the best way to store dimensions in a Database. Some objects have Length, width, height & depth. Some have length and width only. How to store these data properly in the database?

Answer 1

You relate the object with the Dimension type if you want it normalized.

So if I had an object that had length and width only

Object1 Width  10ft
Object1 Length 20ft

Many side table, the many being the type of dimensions, the one side being the Object.

Here is another example with what you gave Length, Width, height, Depth:

Object2 Width 10ft
Object2 Length 10ft
Object2 Height...
Object2 Depth...

The key here is you have a one side table (the object) pointing to a many side table (the dimensions). Some objects can have a dimension others don’t have any dimension (a point for example). I don’t know your table layout but you could have something to this effect:

Object
ObjectID

Dimension
DimensionID

ObjectDimension
ObjectID
DimensionID
Value

INSERT INTO Object(ObjectID) VALUES("Square");
INSERT INTO Object(ObjectID) VALUES("Point");

INSERT INTO Dimension(DimensionID) VALUES("L"); //for length
INSERT INTO Dimension(DimensionID) VALUES("W"); //for width

INSERT INTO ObjectDimension(ObjectID, DimensionID, Value) VALUES ("Square", "L", 5);
INSERT INTO ObjectDimension(ObjectID, DimensionID, Value) VALUES ("Square", "W", 5);