Why do roles and schemas have (mostly) the same name?
This has confused me in the past since they have the same names. Why is this?


I think this is simply becuase of convention, it is easier to identify the owner of the schema. 

Defualt schemas dbo, INFORMATION_SCHEMA, sys schemas are belongs to dbo, INFORMATION_SCHEMA, sys users respectively and these are inherited from model database.

INFORMATION_SCHEMA and sys are used to store system objects so that we can't select to store user-defined objects. dbo is the default schema so we don't need to select it. 

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