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The shop where I work asked me to cost a project using Perl as the back end for a T1 sales feed into an Oracle DB. They wanted to know if they could buy a package to do this. After a little research, I fell over the DBI. They were amazed at the "cost", and delighted with the speed.

I finally got the book about a week ago. Lo and behold, it also covered flat files. A large part of this shop's income comes from a custom doc library, flat files exported from many different DBs. So not only did the book aid with optimising the script I'd already written for the Oracle interface, but it's going to make all our lives easier for the next release of their commercial app.