Why Fact tables should not hold textual information

Although it is theoretically possible for a measured fact to be textual,  one must always avoid having it as part of fact table in dimensional modelling.

Textual information is mostly about the description of something. Therefore they are non-additive. They must be pushed to dimension tables as we do not want to store redundant textual information in fact tables.

As per Ralph Kimball, analysing a true textual face is next to impossible due to the unpredictable context of a text fact.

Also, fact tables take up around 90 percent of the space in dimensional databases. Given the space utilization,  it is best to delegate text information to dimension tables.

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