Transactions_

Transactions let you stage multiple database operations and apply them together, atomically. Use transactions to keep related changes consistent, even when they span multiple databases and collections.

How transactions work

1. Call the createTransaction method to create a transaction. This will return a transaction model, including its ID.
2. Stage operations by passing the transactionId parameter to supported document, bulk, and atomic numeric methods. You can stage many operations at once with the createOperations method.
3. Call the updateTransaction method to commit or roll back.

On commit, Appwrite replays all staged logs in order inside a real database transaction. Staged operations see earlier staged changes (read your own writes). If any affected document changed outside your transaction, the commit fails with a conflict.

Limits

The maximum number of operations you can stage per transaction depends on your plan:

Create a transaction

Call the createTransaction method to begin. It returns a transaction model that includes $id. Pass this ID as transactionId to subsequent operations.

Stage operations

Add the transactionId parameter to supported methods to stage them instead of immediately persisting.

When you pass transactionId, Appwrite writes the operation to an internal staging area. The target collection is not modified until you commit the transaction.

Stage single operations

Create, update, upsert, delete, and atomic numeric operations accept transactionId, as well as their bulk versions (createDocuments, updateDocuments, upsertDocuments, deleteDocuments).

Stage many with createOperations

Use the createOperations method to stage multiple operations across databases and collections in a single request:

Each operation object has this shape:

[
  {
    "action": "create|update|upsert|increment|decrement|delete|bulkCreate|bulkUpdate|bulkUpsert|bulkDelete",
    "databaseId": "<DATABASE_ID>",
    "collectionId": "<COLLECTION_ID>",
    "documentId": "<DOCUMENT_ID>",
    "data": {}
  }
]

Provide data for each action (createOperations)

Create, update, and upsert

Pass a raw data object.

{ "name": "Walter" }

Increment and decrement

Pass a value and optionally min/max bounds.

{ "value": 1, "min": 0, "max": 1000, "attribute": "<ATTRIBUTE_NAME>" }

Bulk create and bulk upsert

Pass an array of raw data objects.

[{ "$id": "123", "name": "Walter" }]

Bulk update

Pass queries and the data to apply.

{ "queries": [{"method": "equal", "attribute": "status", "values": ["draft"]}], "data": { "status": "published" } }

Bulk delete

Pass queries to select documents to delete.

{ "queries": [{"method": "equal", "attribute": "archived", "values": [true]}] }

Commit or roll back

When you are done staging operations, call the updateTransaction method to finalize the transaction.

Handle conflicts

On commit, Appwrite verifies that documents affected by your transaction haven't changed externally since they were staged. If a conflicting change is detected, the commit fails with a conflict error. Resolve the conflict (for example, refetch and re-stage) and try again.