actually it's a pipe delimited Unicode file, but don't worry about that

That is your main problem. Move to a relational database (SQL) and your problem is simplified to simple SQL syntaxt.

You'll be better off with a lightweight SQL database like DBD::CSV or DBD::SQLite everytime (if you cannot afford Mysql/Pgsql and the like).

In reply to Re: Multiple date ranges by Anonymous Monk
in thread Multiple date ranges by AndyH

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