But the Database for Locate need to be Updated every time you make a Search if your System has been Changed after the last Update.
Here below you find the command to manually update it on Mac and Linux.
a) On a Mac open a Terminal session and execute:
sudo /usr/libexec/locate.updatedb
b) On most Linux system you can update your database by:
sudo /usr/bin/updatedb
You will need to Wait until your command will be Executed...