Replace text dg command line di linux

We are going to use the following syntax to find and replace a string of text in a file:
# sed -i ’s/[orginal_text]/[new_text]/’ filename.txt
Say you have a file called “database.txt” with numerous instances of the IP address of your database server in it. You have just switched to a new database server and need to update it with the new server’s IP address. The old IP address is 192.168.1.16 and the new one is 192.168.1.22. Here’s how you go about it:
# cat database.txt
LOCAL_DATABASE = 192.168.1.16
LOCAL_DIR = /home/calvin/
PROD_DB = 192.168.1.16
# sed -i ’s/192.168.1.16/192.168.1.22/g’ database.txt
# cat database.txt
LOCAL_DATABASE = 192.168.1.22
LOCAL_DIR = /home/calvin/
PROD_DB = 192.168.1.22