apache / apache/iceberg-python

Databricks Iceberg REST catalog doesn't support multiple snapshots per transaction

Ouverte
#3,076 1 commentaire 1 réaction 0 personnes assignées Voir sur GitHub
Langage dominant
Python
Étoiles
1.1k
Forks
581
Merge moyen
1 j 17 h
PR mergées (30 j)
78

Description

### Apache Iceberg version

0.10.0 (latest release)

### Please describe the bug 🐞

When connecting with the databricks / unity iceberg REST catalog to write data using pyiceberg, commits fail at `.commit_transaction()` if the transaction contains several snapshots:
`pyiceberg.exceptions.CommitFailedException: CommitFailedException: Failed to commit to the table, requirement failed: Adding multiple snapshots in a single update is not supported.`

This is tricky, since some of the higher-level operations use transactions, but also the "primitives" can fail if a delete happens to contain 2 snapshots (`.update_snapshot()` is called in two places in the delete method).
However these failures might not appear on the happy path but only if eg another writer process has modified the table and the pyiceberg writer then fails because that triggers two snapshots in a transaction

Assuming databricks doesn't intend to bring multi-snapshot transactions into their iceberg rest catalog, would it be possible to add full "autocommit" support to pyiceberg, such that each snapshot can get committed indiviudually?
The transactions would loose their point, but at least one can then again use pyiceberg with unity's iceberg rest reliably

Steps to reproduce:
- Connect to Databricks iceberg REST using pyiceberg
- Open a transaction
- perform operations that generate 2 or more snapshots
- Attempt commit

### Willingness to contribute

- [ ] I can contribute a fix for this bug independently
- [ ] I would be willing to contribute a fix for this bug with guidance from the Iceberg community
- [x] I cannot contribute a fix for this bug at this time

Guide de contribution

Aucun guide de contribution indexé pour ce dépôt

Piste de recherche

Commencez par reproduire l’échec avec le Databricks ou Unity Iceberg REST catalog au moyen d’une transaction contenant plusieurs snapshots. Suivez .commit_transaction(), les deux appels à .update_snapshot() dans la méthode delete et le comportement de la transaction environnante ; le travail sera considéré comme terminé lorsque pyiceberg pourra valider de manière fiable des opérations compatibles lorsque le catalog rejette plusieurs snapshots par transaction.

Rédigé par le modèle d'indexation à partir du texte de l'issue.

Évaluation

Stack technique
python
Domaine
databases
Type d'issue
Bug
Difficulté
5/5
Temps estimé
Plus d'une semaine
Activité
Calme
Clarté
Plutôt claire
Accessibilité débutants
35/100

Recevez les nouvelles issues par e-mail

Un résumé court des issues GitHub adaptées aux débutants.