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 exists:
s1:
[] enwiki
s2:
[] eowiki
[] fiwiki
[] idwiki
[] plwiki
[] ptwiki
[] trwiki
s3:
[] alswiki
[] bawiki
[] bewiki
[] bnwiki
[] bswiki
[] cawikinews
[] cewiki
[] ckbwiki
[] de_labswikimedia
[] dewikiquote
[] dewiktionary
[] elwikinews
[] en_labswikimedia
[] enwikibooks
[] enwikinews
[] eswikibooks
[] eswikinews
[] fawikinews
[] flaggedrevs_labswikimedia
[] frwikinews
[] hewikisource
[] hiwiki
[] iawiki
[] iswiktionary
[] kawiki
[] lawikisource
[] mediawikiwiki
[] mkwiki
[] plwikisource
[] plwiktionary
[] ptwikibooks
[] ptwikinews
[] ptwikisource
[] ruwikinews
[] ruwikiquote
[] ruwikisource
[] ruwiktionary
[] siwiki
[] sqwiki
[] srwikinews
[] tawikinews
[] test2wiki
[] testwiki
[] trwikiquote
[] ukwiktionary
[] vecwiki
[] zh_classicalwiki
s5:
[] dewiki
s6:
[] frwiki
[] ruwiki
s7:
[] arwiki
[] eswiki
[] fawiki
[] huwiki
[] metawiki
[] ukwiki
ALTER to run: `ALTER TABLE /*$wgDBprefix*/flaggedrevs ADD INDEX (fr_user);`