mirror of
https://we.phorge.it/source/phorge.git
synced 2024-12-23 05:50:55 +01:00
3ad727ba78
Summary: Ref T12987. I was focused on the RefCursor table and overlooked that we need some care on this key. It's currently possible to run `bin/storage upgrade --no-adjust`, then start Phabricator, and end up with duplicate records in this table. If you try to run `bin/storage adjust` later, it will try to add the unique key but fail. This is unusual for normal installs (they usually do not use `--no-adjust`) but we do it in the cluster and I did this exact thing on `secure`. Normally, to avoid this, when a new table with a unique key is introduced, we also add a migration to explicitly add that key. This is mostly harmless in this case. Fix this mistake (force the table to contain only unique rows; add the key) and try using `LOCK TABLES` to make this atomic. If this doesn't cause problems we can use this in similar situations in the future. The "alter table may unlock things" warning comes from here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables.html It seems like it's fine to issue `UNLOCK TABLES` even if you don't have any locks, so I think this script should always do the right thing now, regardless of ALTER TABLE unlocking or not unlocking tables. Test Plan: Ran `bin/storage upgrade -f`, saw table end up in the right state. I'll also check this on `secure`, where the starting state is a little messier. Reviewers: amckinley Reviewed By: amckinley Maniphest Tasks: T12987 Differential Revision: https://secure.phabricator.com/D18623
52 lines
1.3 KiB
PHP
52 lines
1.3 KiB
PHP
<?php
|
|
|
|
$table = new PhabricatorRepositoryRefPosition();
|
|
$conn = $table->establishConnection('w');
|
|
$key_name = 'key_position';
|
|
|
|
try {
|
|
queryfx(
|
|
$conn,
|
|
'ALTER TABLE %T DROP KEY %T',
|
|
$table->getTableName(),
|
|
$key_name);
|
|
} catch (AphrontQueryException $ex) {
|
|
// This key may or may not exist, depending on exactly when the install
|
|
// ran previous migrations and adjustments. We're just dropping it if it
|
|
// does exist.
|
|
|
|
// We're doing this first (outside of the lock) because the MySQL
|
|
// documentation says "if you ALTER TABLE a locked table, it may become
|
|
// unlocked".
|
|
}
|
|
|
|
queryfx(
|
|
$conn,
|
|
'LOCK TABLES %T WRITE',
|
|
$table->getTableName());
|
|
|
|
$seen = array();
|
|
foreach (new LiskMigrationIterator($table) as $position) {
|
|
$cursor_id = $position->getCursorID();
|
|
$hash = $position->getCommitIdentifier();
|
|
|
|
// If this is the first copy of this row we've seen, mark it as seen and
|
|
// move on.
|
|
if (empty($seen[$cursor_id][$hash])) {
|
|
$seen[$cursor_id][$hash] = true;
|
|
continue;
|
|
}
|
|
|
|
// Otherwise, get rid of this row as it duplicates a row we saw previously.
|
|
$position->delete();
|
|
}
|
|
|
|
queryfx(
|
|
$conn,
|
|
'ALTER TABLE %T ADD UNIQUE KEY %T (cursorID, commitIdentifier)',
|
|
$table->getTableName(),
|
|
$key_name);
|
|
|
|
queryfx(
|
|
$conn,
|
|
'UNLOCK TABLES');
|