Oracle experience (1)

Install:

Oracle installation has many tutorials on the Internet, which are explained in detail. I will not go into details here. I only provide two links, which may be helpful: Oracle Installation and simple configuration. free installation of Oracle client and PL/SQL

 

Problem:

This problem occurs during the experience of Oracle. Here we will make a simple arrangement.

Question 1:

Problem description:

In the DOS window, run the sqlplus/nolog command to log on to Oracle. The result is: "sqlplus is not an internal or external command ",:

Solution:

Computer → properties → advanced → environment variable, add the file path of sqlplus.exe of Oracle 11g(server terminal) in path. For example, if my Path is D: \ app \ huaying \ product \ 11.2.0 \ dbhome \ BIN, add the Path of the above file to the Path, of course, the premise is that sqlplus must be in the D: \ app \ huaying \ product \ 11.2.0 \ dbhome \ BIN directory. If you do not have an exe file, you can only reinstall it.

Problem Analysis:

We know that Path refers to the Path. It is like a global variable. After the configuration is complete, you can find it in this Path if you execute the sqlplus command on this computer or user.

Question 2:

Problem description:

After installing Oracle, I found that I forgot the password of the system and sys users, so I tried a lot of self-guessed passwords under the DOS command, the error message "Oracle 11g the account is locked" may be reported because you have entered too many wrong passwords ".

 

Solution:

Step 1: Use sqlplus to log on to the system

Step 2: connect to sysdba

Step 3: Unlock

Step 4: change the password

Problem Analysis:

Here are some reasons why the user name may be locked: ① common sense fails to log on multiple times (the password may be incorrect); ② the user is locked by the Administrator manually; ③ The user password expires, the password is not modified on time, and so on.

Question 3:

This should not be a problem, but it should be a talk about some feelings when importing scripts. When importing a script, it seems to be a very simple action, but it has experienced a lot in the process of export. Everything should come from your own ignorance!

The first step is to create a user, create a tablespace, modify the user's default tablespace, and authorize the user. Then, the real script is imported. It is not a problem to write scripts that are familiar with SQL statements. However, many problems occur during the script generation process by Powerdesigner. One of the reasons is that we did not modify the data Syntax of Powerdesigner. Therefore, all the generated scripts are SQL, many cannot be used in Oracle, especially when some keywords are easy to report errors.

 

Summary:

The experience of Oracle is painful and happy.