Some easy to forget little knowledge points

Since it is often done on Linux servers, some of the frequently used commands are always forgotten and are now logged:

1. Often forget the use of a command, the habit of using man, but use Help to query the use of this command is more intuitive.

2.history, use this command to clean up some very sensitive information (such as passwords, user names, etc.).

History-c means cleaning up all of the history records.

history-d num Specifies to clean up that history

　　In the/root/.mysql_history file, there are a number of previously executed MySQL commands

3.tree view some files in a directory to see more intuitive

4. Mkdir/data2/{2,3}.log creates 2.log and 3.log consecutively under the Data2 directory

5. On the MySQL command line interface, use prompt \[email protected] \r:\m:\s--> to change the command line interface of MySQL so that it can be clearly identified on that machine, the effect is as follows:

1 mysql> prompt \[email protected] \r:\m:\s-->2set'\[email protected] \ r:\m:\s-->'3:4:  5:----

Some easy to forget little knowledge points