Recently, I reinstalled my computer (dual-system windows10+ubuntu16), and upgraded my software. As a result, I installed the latest oracle12c, and a series of problems appeared. I don’t like to torment, L once said that I like what torment, waste of time, money can solve, let yourself relax. After installing Oracle12C this time, the login name and password are not correct, so it took me a whole morning.

See this article for the installation and use of oracle12c. Oracle 12C Windows Installation, Introduction and Simple Use

1.0 SQL Plus login, username/password invalid; Login denied problem. Oracle the network Adapter could not establish the connection.

The problem is shown as follows:

If you have this problem, you’ve come to the right place. Hee hee, it took me all morning to solve it.

I read more than 10 tutorials on the Internet, and finally got it done under my own contingency. This is to write a blog, convenient encounter the same problem small partners.


See article: 12c Creating public and local users

So here’s the solution: prefix the username with c##

create user c##master identified by zxk123456789;
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The results of

User C##MASTER created.
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Important permissions, Oracle permissions are important, I like God permissions

grant connect,resource,dba to c##master;
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The results of

Grant success.Copy the code

For more information, see Oracle-04- Creating user & New user authorization with SQL*PLUS

Format for:

 update user$ set name='MY_USER2' where name='MY_USER1';
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I seem to have failed:

Perform the following operations in SQLPlus:

SQL> update user$ set name='master' where name='c##master'; Row 0 has been updated. On the client, the error looks like this. SQL error: ORA-00942: table or view does not exist 00942.00000 -"table or view does not exist"
*Cause:    
*Action:
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Prepare to try the following statement:

update dba_users set username='master' where username='c##master';
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Results:

SQL error: ORA-01031: permission insufficient 01031.00000 -"insufficient privileges"
*Cause:    An attempt was made to perform a database operation without
           the necessary privileges.
*Action:   Ask your database administrator or designated security
           administrator to grant you the necessary privileges
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Have thought SQL plus login, use dba to execute above statement, result

Ora-01031: Insufficient permissionsCopy the code

I think it’s still about access.

Change password:

The format is as follows: ALTER user User name identified by New password;Copy the code

My operation is as follows:

alter user c##master identified by mm123456;
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Results:

User C##MASTER has changed.

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SQL Plus link successful.

Please enter user name: c##masterEnter password: connect to: Oracle Database 12C Enterprise Edition Release 12.2.0.1.0-64bit ProductionCopy the code