export const meta = {
  title: `Troubleshooting`,
  description: `Add authorization rules to your GraphQL schema to control access to your data.`,
};

## Deploying multiple index changes at once

You can make `@index` updates on one "amplify push". Under the hood, Amplify CLI needs to locally sequence multiple individual deployments to your DynamoDB table because each Global Secondary Index (GSI), managed by `@index`, change requires time to create the new index.

If your deployment fails locally when updating multiple GSIs, you'll have the ability to run:

- `amplify push --iterative-rollback` to rollback the last-known-good state
- `amplify push --force` to rollback the last-known-good state and try redeploying your changes again using.

```console
Attempting to mutate more than 1 global secondary index at the same time.
```

If you're running into the error above during `amplify push`, it is likely that you don't have this feature enabled. To enable multiple GSI updates, set the "enableIterativeGsiUpdates" feature flag to true in your `amplify/cli.json` file.

## Backfill OpenSearch index from DynamoDB table

When you add `@searchable` to a `@model` type with existing data, then you need to backfill the OpenSearch index. Download the following Python script to help you backfill your OpenSearch index:

[DynamoDB to OpenSearch backfill script](https://raw.githubusercontent.com/aws-amplify/amplify-category-api/main/packages/graphql-elasticsearch-transformer/scripts/ddb_to_es.py)

The script creates an event stream of your DynamoDB records and sends them to your OpenSearch Index. Execute the script with the following parameters to initiate the backfill:

|Parameter|Description|Required|
|---------|-----------|--------|
|`--rn`   | DynamoDB table region. See [AWS Regions](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Concepts.RegionsAndAvailabilityZones.html) for available options |Yes|
|`--tn`   | DynamoDB table name. Format: `{@model type name}-{AppSync API ID}-{Amplify environment}`|Yes|
|`--lf`   | ARN of the "DynamoDB to OpenSearch streaming" Lambda function. Format: `arn:aws:lambda:{region}:{AWS Account ID}:function:amplify-{Amplify project name}-{Amplify environment}-{Random string}-OpenSearchStreamingLambd-{Random string}`|Yes|
|`--esarn`| ARN of the DynamoDB table stream. Format: `arn:aws:dynamodb:{region}:{AWS Account ID}:table/{@model type name}-{AppSync API ID}-{Amplify environment}/stream/{Table creation date}`|Yes|
|`--ak`   | AWS Access Key ID. This is used to authenticate with your AWS account in case no local AWS profile is set up. | No|
|`--sk`   | AWS Secret Access Key. This is used to authenticate with your AWS account in case no local AWS profile is set up. | No|
|`--st`   | AWS Session Token. This is used to authenticate with your AWS account in case no local AWS profile is set up. | No|

In the example below, the `Post` table data in `us-west-2` gets backfilled in the OpenSearch index.

```bash
python3 ddb_to_es.py \
  --rn 'us-west-2' \ # Use the region in which your table and OpenSearch domain reside
  --tn 'Post-XXXX-dev' \ # Table name
  --lf 'arn:aws:lambda:us-west-2:<...>:function:amplify-<...>-OpenSearchStreamingLambd-<...>' \ # Lambda function ARN, find the DynamoDB to OpenSearch streaming functions, copy entire ARN
  --esarn 'arn:aws:dynamodb:us-west-2:<...>:table/Post-<...>/stream/2019-20-03T00:00:00.350' # Event source ARN, copy the full DynamoDB table ARN
```

## Index with multiple sort key fields

When you add an `@index` directive with 2 or more sort key fields, you will need to backfill the new composite sort key for existing data. With `@index(sortKeyFields: ["status", "date"])`, you will need to backfill the `status#date` field with composite key values made up of each object's `status` and `date` fields joined by a `#`. You do not need to backfill data for `@index` directives with zero to one sort key field(s).