I wrote the following python script to read xlsx. It's extremely basic, but works very well for me. http://github.com/brendano/tsvutils/blob/master/xlsx2tsv h

I wrote the following python script to read xlsx. It's extremely basic, but works very well for me. http://github.com/brendano/tsvutils/blob/master/xlsx2tsv http://github.com/brendano/tsvutils/blob/master/xlsx2tsv I've never tried it on a 20,000 row file. I suspect it would work. A really large file might need to switch to a streaming XML parser, but probably Excel itself wouldn't handle that use case too well.