Database Tables without Relationships in the Schema

N2IT

Is this common? In our database we have ~32% of all tables are standalone with no relationship. Some are part of an ETL which would explain why they aren't related, but still that's a lot! This is a data warehouse environment with some transactions going on. Is this common?

phoeneous

What platform?

NotHackingYou

Yes, it is common.

NightShade03

Yes it is common. You'll also find that during ETL certain values need to be combined leading to tables like this (often called a contingency table -> Contingency table - Wikipedia, the free encyclopedia).

Depending on the platform and DW tools in use I've seen many of these tables usually stored in a caching server like Redis, or a NoSQL platform. Sometimes ACID compliant platforms are used because that is were the expertise within the organization lies.

N2IT

SSMS 2008 Yeah I am seeing a lot of tables not hard related it's confusing to say the least. I found some nice sys tables that can provide a ton of information, basically building a data dictionary.