Why was PyTables born?
Because, back in August 2002, one of its authors (Francesc Alted) had a need to save lots of hierarchical data in an efficient way for later post-processing it. After trying out several approaches, he found that they presented distinct inconveniences. For example, working with file sizes larger than, say, 100 MB, was rather painful with ZODB (it took lots of memory with the version available by that time).
