Data Persistence

My programs can share their data, either with other programs or with future invocations of themselves. To make that possible, I store the data outside of the program’s memory and then read it from that source to recreate it. I can put that data in a file or a database, send it over a network connection, or anything else I want to do with it.

I can even share data between different programs. For anything except for simple applications, I’d probably want to use a robust database server and the DBI module. I won’t cover proper database servers such as MySQL, PostgreSQL, or Oracle. Perl works with those through DBI, and there’s already a great book for that in Further Reading,” at the end of the chapter. This chapter is about lightweight techniques I can use when I don’t need a full server backend.