Is there more secure way of using DBI than putting the password in plain text in script?
There are several, depending on your configuration (e.g., your database). You can
- Read the usename and password out of a file that's not accessible to the web server. This protects against web server exploits that might make the script visible. Such exploits were a problem several years back, and now affect only old, unpatched servers.
- Configure your database server to only accept requests that come from specific IP addresses (e.g., 127.0.0.1). This limits the damage that might happen if someone hacked your script remotely, but doesn't help if they hack the box.
- Defer all direct database access to a middle-tier process that prompts for a user at startup. Some high-security shops actually do this, which makes life a nuisance for support staff when the power fails.
- Defer all direct database access to a middle-tier process that lives on a separate box, and which speaks a narrow, application-specific protocol. This limits the damage if someone hacks your web server box.
A while back I gave some prior advice to a similar question here. You might find other info in that thread useful.