A database is the main container, it contains the data and log files, and all the schemas within it. You always back up a database, it is a discrete unit on its own.
Schemas are like folders within a database, and are mainly used to group logical objects together, which leads to ease of setting permissions by schema.
drop schema test1
Msg 3729, Level 16, State 1, Line 1
Cannot drop schema 'test1' because it is being referenced by object 'copyme'.
You cannot drop a schema when it is in use. You have to first remove all objects from the schema.
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