I'm not sure if DBI::table_info and DBI::column_info are a pipe dream or not.. From what I've seen around CPAN, any code that needs access to database schemas has employed DBD-specific code/queries for that purpose. I'd would be very interested to see examples of table_info and column_info that work transparently across many DBDs.

Here are queries you can execute to fetch info about columns and tables, for the drivers I know how:

MySQL:
  show tables
  describe TABLE_NAME

SQLite:
  select name from sqlite_master where type='table'
  pragma table_info('TABLE_NAME')
[download]

You will also have better luck with table_info and column_info if you look at their usage in the DBI docs -- they return active statement handles, not a list of things. (The tables method does return a simple list, but your usage of it (no arguments) is deprecated -- also note that for many drivers, the tables method returns a lot of system tables, views, etc.. probably more than you want).