mirror of
https://we.phorge.it/source/phorge.git
synced 2024-11-09 16:32:39 +01:00
Guarantee the key_position
key is created properly
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
This commit is contained in:
parent
94ab0c9afb
commit
3ad727ba78
1 changed files with 52 additions and 0 deletions
52
resources/sql/autopatches/20170918.ref.01.position.php
Normal file
52
resources/sql/autopatches/20170918.ref.01.position.php
Normal file
|
@ -0,0 +1,52 @@
|
|||
<?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');
|
Loading…
Reference in a new issue