Here is a collection of some of the observations I've made about page history oddities. I find out if there are page histories to merge by checking deleted contributions of early editors, and checking articles on place name lists like List of urban areas by population or national place name lists. Note that I'm not a developer, and only have admin access; therefore I can only find histories that are either in the main database or in the deleted archives. Feel free to add any page history oddities to this user page.
Pages whose history has been lost
Page history started to be reliably kept and dated after the conversion to a MySQL database in early 2002 (see Wikipedia:Usemod article histories for caveats). Therefore, all history from that time onwards should be theoretically accessible. However, some page history has disappeared entirely due to moves and deletions. The following situation is typical:
- Page A is moved to Page B by cut and paste, either before the move function was added in August 2002 or by a user who wasn't aware of the page move function.
- Page B is moved back to page A with the move function, thus deleting page A's old history.
- The deletion archives are cleared, meaning that the deleted history of page A is gone permanently. The deletion archives were last cleared on 8 June, 2004 in a database crash, and were previously cleared on 3 December 2003.
Therefore any page history deleted before June 8, 2004 is gone forever. Some very early revisions appear in Nostalgia Wikipedia, but the old revisions are not in the main English Wikipedia database. The following articles have missing history which seemingly cannot be restored:
- Glasgow
- Canberra
- Queensland
- Port Arthur massacre (Australia) (the deleted history is probably at Port Arthur Massacre)
- Marseille (the deleted history maybe at Marseilles)
- Geelong, Victoria
- Demographics of Australia
- İzmir (a copyvio was introduced, the whole article was deleted, then the pre-copyvio text was replaced without the page history - see this edit at Talk:İzmir)
Some close calls
I have restored some page history that was deleted due to page moves. Most of these operations were trivial, like this one at Accra. However, the following are interesting cases and show the problems with cut and paste moves. See my logs dealing with:
If the deletion archives had been cleared out or there was a bad database crash, the page histories of Quechua, Tesla (unit) and Tesla may have become permanently inaccessible.
Revision ID numbers
When a revision is added to the database, it gets an ID number which is one more than the previous revision. Revision ID numbers are therefore a reasonable way to estimate the date of a revision. However, before Wikipedia was upgraded to MediaWiki 1.5 in late June 2005, if a revision was deleted and undeleted, it would get a new ID number as if it was a brand new revision. For example, the first recorded edit to the article Wikipedia has an ID number of 13,435,822, even though the edit was made in December 2001, because the article was deleted and restored before June 2005. For comparison, the revision with the previous ID number of 13,435,821 was made in May 2005. The inconsistent ID numbers can cause probllems when the software tries to decide the number of revisions between two edits, as the system for detecting intermediate revisions works by revision ID. An example is this edit to Talk:Netherlands.
Strange edit times
Here are some diffs showing the consequences of the clock being reset: [
- Wikipedia:Articles for deletion/List of Human Atrocities
- Wikipedia:Administrators' noticeboard/Incidents
- Talk:Motorway
- User talk:Kim Bruning
- History of knitting
Fun page history facts
- The page Louisville, Kentucky was originally at the title Talk radio/Louisville