Enabling the MYSQLI_CLIENT_FOUND_ROWS option will make affectedRows() after UPDATE queries reflect the number of matching rows, regardless of whether any column values had to be changed. This means if the row was already in the state the query wanted to ensure, it will still be counted.
This is, I think, what callers want to know and is consistent with how Postgres, SQLite, and MSSQL behave already.
Change 524099 had a related patch set uploaded (by Krinkle; owner: Aaron Schulz):
[mediawiki/core@master] rdbms: set MYSQLI_CLIENT_FOUND_ROWS in DatabaseMysqli
Change 526577 had a related patch set uploaded (by Krinkle; owner: Aaron Schulz):
[mediawiki/core@master] Clean up use of IDatabase::affectedRows() in WikiPage::updateRedirectOn()
Change 526587 had a related patch set uploaded (by Krinkle; owner: Aaron Schulz):
[mediawiki/extensions/FlaggedRevs@master] Clean up the use of IDatabase::affectedRows()
Change 526595 had a related patch set uploaded (by Krinkle; owner: Aaron Schulz):
[mediawiki/extensions/Newsletter@master] Cleanup use of IDatabase::affectedRows()
Change 526594 had a related patch set uploaded (by Krinkle; owner: Aaron Schulz):
[mediawiki/extensions/PageTriage@master] Cleanup setTriageStatus() and IDatabase::affectedRows() usage
Change 526578 had a related patch set uploaded (by Krinkle; owner: Aaron Schulz):
[mediawiki/core@master] Cleanup JobQueueDB::recycleAndDeleteStaleJobs() use of IDatabase::affectedRows()
Change 526587 merged by jenkins-bot:
[mediawiki/extensions/FlaggedRevs@master] Clean up the use of IDatabase::affectedRows()
Change 526595 merged by jenkins-bot:
[mediawiki/extensions/Newsletter@master] Cleanup use of IDatabase::affectedRows()
Change 526576 had a related patch set uploaded (by Krinkle; owner: Aaron Schulz):
[mediawiki/core@master] Cleanup UserGroupMembership::insert() and make it more atomic
Change 526576 merged by jenkins-bot:
[mediawiki/core@master] Cleanup UserGroupMembership::insert() and make it more atomic
Looking for CR for the following remaining ones:
Change 526577 merged by jenkins-bot:
[mediawiki/core@master] Clean up use of IDatabase::affectedRows() in WikiPage::updateRedirectOn()
Change 526578 merged by jenkins-bot:
[mediawiki/core@master] Cleanup JobQueueDB::recycleAndDeleteStaleJobs() use of IDatabase::affectedRows()
Change 524099 merged by jenkins-bot:
[mediawiki/core@master] rdbms: set MYSQLI_CLIENT_FOUND_ROWS in DatabaseMysqli
This is significantly less useful than the old behavior. Affected_rows is typically used to either skip expensive cache purges when nothing actually changed, or signal to the user whether they actually managed to change something. (Why would a caller care about rows matched but not changed?)
I guess consistency trumps utility here... but if there was a way to change the other engines in the other direction instead, that would be much preferable.
Change 530564 had a related patch set uploaded (by Gergő Tisza; owner: Gergő Tisza):
[mediawiki/core@master] Fix IDatabase::affectedRows() documentation
Working around the new behavior is not hard but ugly:
// old code $db->update( 't', [ 'c1' => $v1, 'c2' => $v2, 'c3' => $v3 ], [ 'id' => 1 ], __METHOD__ ); // new code $db->update( 't', [ 'c1' => $v1, 'c2' => $v2, 'c3' => $v3 ], [ 'id' => 1, $db->makeList( [ 'c1 != ' . $db->addQuotes( $v1 ), 'c2 != ' . $db->addQuotes( $v2 ), 'c3 != ' . $db->addQuotes( $v3 ), ], IDatabase::LIST_OR ), ], __METHOD__ );
and then a lot more complicated than that if the values can be null or array. I wonder if it would make sense to have a helper function / flag for automatically adding that kind of check...
Change 530564 merged by jenkins-bot:
[mediawiki/core@master] Fix IDatabase::affectedRows() documentation
SqlBagOStuff::changeTTL(), for example, only cares if there was a row. Callers have more control by being able to use the WHERE clause to decide when to care about column values changing or not.
The code example above could probably be simplified:
$set = [ 'c1' => $v1, 'c2' => $v2, 'c3' => $v3 ]; $db->update( 't', $set, [ 'id' => 1, 'NOT (' . $db->makeList( $set, IDatabase::LIST_AND ) . ')' ], __METHOD__ );
Change 526594 merged by jenkins-bot:
[mediawiki/extensions/PageTriage@master] Cleanup setTriageStatus() and IDatabase::affectedRows() usage