As the name suggests, bridge table is used to link tables when direct linking does not make sense. Usually used in a little complecated senarios when we have many to many relations between 2 tables.
Example: Consider we have multiple customer linked to a single bank account balance. Putting multiple customer keys in that fact would create obvious problems in the fact table.
Bridge table is also used sometimes to manage variable hierarchies. For e.g. to maintain one primary customer and one or more secondary customers.
Bridge table come to rescue in such situation, but just like outrigger dimension don't use it too much. Remember, every query has to pay toll to navigate the bridge.
Although, it is not a dimension but I personally call it Bridge dimension because it has many properties of a dimension.
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