Is using shell_exec safe?

Safety probably depends on how you have coded it and who can get to it.  With all of the MySQL functions built into PHP, what would you be using it for?

Thank you.

Safety probably depends on how you have coded it and who can get to it.

I'm hardly coding it, means i'm writing it as follows:
shell_exec(command);
Where COMMAND is the read command that I coded [not a variable and not containing and input from the user].
So is this safe?

I want to create DB, Clone DB.

Sorry, What do you mean by running command from a file?

shell_exec normally uses a text variable as the command.  http://php.net/manual/en/function.shell-exec.php  That is essentially the same as running it from a file.

To create and Clone DB is not very useful if no one has privileges to use it.  Creating users and privileges is a separate operation from creating the database.

Note also that you usually have to have 'root' privileges to do any of these things.

I'm normally able to create users and grant privileges on the new created DB using shell command.
So no problem in this point.

The main point for me is the security of using shell_exec to do this.