Difference between login and user on sql server

Question

CREATE USER [anc] WITHOUT LOGIN WITH DEFAULT_SCHEMA=[anc]
GO

what is the difference between user and login.

I don’t understand how we create such users?

Answer 1

Logins are server (level objects). Their correct name is "server principles" (see sys.server_principals). To access the servers, server privileges are granted, such as create databaseor permissions view server state.

Users are database objects that are correctly called "database principals" (see sys.database_principals). They are the recipients of database permissions, such as create tableor select.

1--1 SID, , sysadmin dbo.

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Answer 2

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