Versioning
What is time travel?
Time travel queries a prior version of a table, so you can see rows and computed outputs as they were after an earlier change.
Updated
How it works
- Each change creates a version.
- A query can name that version.
- You compare it with the current rows when a result looks wrong.
What it is not
It is not git for notebooks, and it is not restoring a whole database from a backup.
time travel: this, and the thing it is confused with
| This | Not this | |
|---|---|---|
| Unit | A table version | A disk snapshot of the server |
| Sees | Rows and computed values then | Only source files |
| Use | Debug a change | Disaster recovery |
Where Pixeltable fits
Pixeltable versions tables. history() lists the versions, pxt.get_table('t:N') reads one, and revert() undoes the latest.
Questions
How does time travel work?
Each change creates a version. A query can name that version. You compare it with the current rows when a result looks wrong.
What is time travel often confused with?
It is not git for notebooks, and it is not restoring a whole database from a backup.
Next step
Install the Pixeltable skill, or sign up for Cloud and run the same file on a hosted database.