MySQL tutorial: mysql concat() function
The MySQL CONCAT function accepts one or more string parameters and concatenates them into a string....
How to move files or directories in linux/unix
To move files or directories, you can use the mv command. It supports moving files or directories to another directory, and also supports regular matching....
How to rename directory and file in linux/unix
To rename directories and files, we can use the linux mv command. You can also use the awk command to rename rule directories or files...
java tutorial: install Java JDK and Maven on Mac
Install Java JDK and Maven on mac os: 1) Download and install files from the official website; 2) Install using homebrew package manager....
list directory with ls command in linux/unix
In linux, with the ls command -d option, you can only list the directories of the current directory, not recursively....
What command is linux ll?
Linux ll is not a command provided by the linux system. It is usually the command alias we set. Generally, the ls -l command is...
Sort files or folders by size with ls command in linux/unix
The Linux ls -S option can be sorted by size from largest to smallest, or the ls -rS option can be sorted by size from...
How to display the file size in megabytes with ls in linux/unix
Display the file size in megabytes, which can facilitate us to browse the file storage size. Syntax: ls -lh , to display the file size...
How to list hidden files and folders in linux/unix
In linux/unix, when it comes to listing files and folders, everyone will think of the ls command. Yes, there are many options for the ls...
List directories recursively in linux/unix
Recursive listing of directories can help us begin to understand the current directory structure. In linux/unix, we can use any of the following commands to...
mkdir recursively create directories in linux/unix
Creating directories recursively can help us greatly improve efficiency during development. In linux/unix, we can use the mkdir command to recursively create directories and subdirectories...
rm delete recursively in linux/unix
How to use the rm command to delete files and directories recursively in linux/unix. Syntax Examples In the following example, recursively delete data folder: First...
How to show the currently logged in user in linux/unix
Show the current logged-in users is a must in linux/unix, which can help us determine which users are using the terminal window to log in...
awk tutorial: awk multiple conditions
Awk supports if else conditions judgment, and multiple conditions operations with && (and) or || (or) can be used....
sed tutorial: sed replace
Sed replace, you can use the sed function: s, replace the text in the file. syntax: ➜ ~ sed 's/regexp/replacement/' file...