Looking for logging into the Alter site and are not getting the correct working link for it? In such a case, you can use the links given here by searching your desired login page in the search box. If the page is present on our website then you will get all the links related to the Alter site. After that you can login as usual with your login credentials.
https://docs.microsoft.com/ja-jp/sql/t-sql/statements/alter-login-transact-sql
http://www.sql-master.net/sql-for-beginners
https://www.techonthenet.com/sql_server/users/alter_login.php
http://www.pine4.net/Memo/Article/Archives/114
https://blogs.yahoo.co.jp/qingyongyujp/49205913.html
https://qiita.com/chatii0079/items/d83f3f50b0c3a185ac7f
https://stackoverflow.com/questions/8329978/cant-alter-login/8329994
https://community.spiceworks.com/topic/1976538-can-i-use-alter-login-to-change-a-sql-authenticated-user-s-sid
http://dba.fyicenter.com/faq/sql_server_2/ALTER_LOGIN_Changing_a_Login_Name.html
https://books.google.co.jp/books?id=cJt5LXLddGgC&pg=PA19-IA167&lpg=PA19-IA167&dq=alter+login
https://www.postgresql.org/docs/9.0/sql-alterrole.html
https://blog.sqlauthority.com/2007/05/03/sql-server-enable-login-disable-login-using-alter-login-change-name-of-the-sa/
https://ss64.com/sql/login_a.html