As noticed in T104686
>>! In T104686#3490006, @jcrespo wrote:
> Apparently, such an opperation runs the query `UPDATE /* MergeUser::mergeDatabaseTables */ flaggedrevs SET fr_user = 'XXXXXX' WHERE fr_user = 'XXXXX'`, which goes over 64 million rows unindexed and not batched (even if no rows are updated). That would be a hard blocker for future runs.
fr_user is unindexed
Wikis where this table is enabled: https://github.com/wikimedia/operations-mediawiki-config/blob/master/dblists/flaggedrevs.dblist
s1:
[x] enwiki
s2:
[x] eowiki
[x] fiwiki
[x] idwiki
[x] plwiki
[x] ptwiki
[x] trwiki
s3:
[x] alswiki
[x] bawiki (not enabled)
[x] bewiki
[x] bnwiki
[x] bswiki
[x] cawikinews
[x] cewiki
[x] ckbwiki
[] de_labswikimedia (not enabled)
[x] dewikiquote
[x] dewiktionary
[x] elwikinews
[] en_labswikimedia (not enabled)
[x] enwikibooks
[x] enwikinews
[x] eswikibooks (not enabled)
[x] eswikinews
[x] fawikinews
[x] flaggedrevs_labswikimedia (not enabled)
[x] frwikinews
[x] hewikisource
[x] hiwiki
[x] iawiki
[x] iswiktionary
[x] kawiki
[x] lawikisource
[x] mediawikiwiki (not enabled)
[x] mkwiki
[x] plwikisource
[x] plwiktionary
[x] ptwikibooks
[x] ptwikinews
[x] ptwikisource
[x] ruwikinews
[x] ruwikiquote
[x] ruwikisource
[x] ruwiktionary
[x] siwiki (not enabled)
[x] sqwiki
[x] srwikinews
[x] tawikinews
[x] test2wiki
[x] testwiki (not enabled)
[x] trwikiquote
[x] ukwiktionary
[x] vecwiki
[x] zh_classicalwiki
s5:
[] dewiki
s6:
[x] frwiki
[x] ruwiki
s7:
[x] arwiki
[x] eswiki (not enabled)
[x] fawiki
[x] huwiki
[x] metawiki (not enabled)
[x] ukwiki
ALTER to run: `ALTER TABLE /*$wgDBprefix*/flaggedrevs ADD INDEX (fr_user);`