Branches
A branch is a full copy of another branch, or of a snapshot, at the moment you create it. Changes on a branch stay on that branch.
Branches don’t merge data back. There is no merge. The flow Lumbung supports is:
- Create a branch from the default branch.
- Run your migration on the branch and test your app against it.
- Run the same migration on the default branch.
- Delete the branch.
Use the schema diff between the two branches to confirm the migration did what you expected before step 3.
Creating a branch
Section titled “Creating a branch”A new branch copies its source with SQLite’s online backup, inside one read transaction. Writers on the source keep going while the copy runs, and the copy holds exactly the transactions committed when it started: never half of one.
A branch can start from:
- any branch of the same database (the default when you name none), or
- a snapshot, which is how restore works.
Operations
Section titled “Operations”| Operation | What it does |
|---|---|
| Rename | Changes the name. The id stays. |
| Reset | Copies the branch’s parent again, throwing away the branch’s changes. |
| Promote | Makes the branch the database’s default. The old default stays as an ordinary branch, still protected until you change that. |
| Delete | Removes the branch and its file. |
| Schema diff | Compares tables, columns, indexes, views and triggers with another branch. |
Waiting for maintenance
Section titled “Waiting for maintenance”Reset, delete and import replace or remove the branch’s file, so they wait for requests already running on the branch to finish. While one waits, new requests on that branch queue behind it for at most a few seconds at a time, then go through, so a long download can’t take the branch offline. If the requests don’t finish within two minutes, the operation fails with busy and nothing changes.
Protected branches
Section titled “Protected branches”A protected branch can’t be deleted or reset. The default branch is always protected. Turn protection on for any branch you want to keep safe.
Expiry
Section titled “Expiry”A branch can expire after a number of days, which suits a branch per pull request. An expired branch is deleted automatically unless it is protected.
Schema diff
Section titled “Schema diff”The diff reads each branch’s schema and reports every table, index, view and trigger that was added, removed or changed. Changed tables list the columns added, removed or altered. Each change carries the DDL from both sides.