forgejo/models/migrations/v1_21/v277.go
JakobDev 14731a34ff
Add index to issue_user.issue_id (#27154)
This fixes a performance bottleneck. It was discovered by Codeberg.
Every where query on that table (which has grown big over time) uses
this column, but there is no index on it.

See this part of the log which was posted on Matrix:
```
2023/09/10 00:52:01 ...rs/web/repo/issue.go:1446:ViewIssue() [W] [Slow SQL Query] UPDATE `issue_user` SET is_read=? WHERE uid=? AND issue_id=? [true x y] - 51.395434887s
2023/09/10 00:52:01 ...rs/web/repo/issue.go:1447:ViewIssue() [E] ReadBy: Error 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
2023/09/10 00:52:01 ...eb/routing/logger.go:102:func1() [I] router: completed GET /Codeberg/Community/issues/1201 for [::ffff:xxx]:0, 500 Internal Server Error in 52384.2ms @ repo/issue.go:1256(repo.ViewIssue)
```
2023-09-21 01:30:48 +00:00

17 lines
292 B
Go

// Copyright 2023 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package v1_21 //nolint
import (
"xorm.io/xorm"
)
func AddIndexToIssueUserIssueID(x *xorm.Engine) error {
type IssueUser struct {
IssueID int64 `xorm:"INDEX"`
}
return x.Sync(new(IssueUser))
}