As far as the melatonin, don't waste your money on it, because it doesn't do anything for you. You'd get just as good result, giving your child pieces of candy, or anything edible really, and telling them that it'll help them sleep, and if they believe it will, it might, just like melatonin does.
Ultimately, all of the data is stored in columns, and metadata is required to identify the columns that function as multidimensional objects. In Oracle Database, you can define a logical multidimensional model for relational tables using the OLAP Catalog or AWXML, as described in Chapter 5..2 The Relational Implementation of the Model. The relational implementation of the multidimensional data model is typically a star schema, as shown in Figure 2-2, or a snowflake schema.
Multiple relationships between tables. A Data Model can have multiple relationships between two tables. To create accurate calculations, Excel needs a single path from one table to the next. Therefore, only one relationship between each pair of tables is active at a time.