Question

Articles in wikipedia get edited. They can grow/shrink/updated etc. What file system/database storage layout etc is used underneath to support it. In database course, I had read a bit on variable length record, but that seemed like more for small strings and not for whole document. Like in file system, files can grow/shrink etc, and I think its done by chaining blocks together. each time, we update a file, not the whole file is rewritten. Perhaps something similar would be done here.

I am looking for specific names,terminologies, may be even how the schema in mysql is defined. (I think wikipedia uses mysql).

Below are links to some writeup on wikipedia architecture, but I am not being able to answer my question from these:

http://swe.web.cs.unibo.it/twiki/pub/WikiFactory/AntonelloDiMuroThesis/Wikipedia-cheapandexplosivescalingwithLAMP.pdf

http://dom.as/uc/workbook2007.pdf

Thanks,

Answer 1

See:

http://www.mediawiki.org/wiki/Manual:Database_layout