What is the purpose of a link table?

The purpose of a link table is to facilitate the association between multiple fact tables in a data model by placing common fields into a new table. This approach helps to resolve issues typically associated with a synthetic key, which arises when two or more fact tables share common dimensions.

By creating a link table, you establish a many-to-many relationship, allowing different fact tables to access the same dimensions without redundancy. The link table keeps the model organized and efficient, ensuring that queries can be executed against multiple fact tables by leveraging shared dimensions without causing ambiguity in relationships.

While other options may mention elements of data integrity, summarization, or high-level overviews, they do not capture the primary function of a link table in enabling the effective data modeling of multiple fact tables through shared attributes.