Step Function - dynamodb query with Boolean Filter

Question

Using Step function AWS SDK integration for querying dynamodb table with key condition and filter condition, below is the query works fine outside of step-function. When trying to save the state machine after adding this, get the below Error.

**Ddb Query**

```
{
  "TableName": "test",
  "ScanIndexForward": true,
  "KeyConditionExpression": "pk = :pk",
  "FilterExpression":"scheduled = :scheduled",
  "ExpressionAttributeValues": {
    ":pk": {
      "S": "test"
    },
    ":scheduled": {
      "BOOL":true
    }
  }
}
```

** Error Saving State Machine **

```
There are Amazon States Language errors in your state machine definition. Fix the errors to continue.

The field "BOOL" is not supported by Step Functions

For more information, see Amazon States Language
```

wongada · Accepted Answer

The optimized service integrations accept BOOL, however there is a difference between how AWS SDK integrations handle request parameters. **If you switch from `"BOOL"` to `"Bool"` it will work.** All parameters for AWS SDK integrations must be in PascalCase.

Source:
> The API action will always be camel case, and parameter names will be Pascal case. For example, you could use Step Functions' startSyncExecution API action and specify the parameter StateMachineArn.

https://docs.aws.amazon.com/step-functions/latest/dg/supported-services-awssdk.html

Uri · Answer

According to [this](https://stackoverflow.com/questions/40461910/aws-dynamodb-query-not-filtering-on-bool-value), you should change 
`":scheduled": {
      "BOOL":true
    }`
to
`":scheduled": true`
Did not try it.

jamessouth · Answer

Querying is not supported in SFN, just [get, put, delete, and update.](https://docs.aws.amazon.com/step-functions/latest/dg/connect-ddb.html)

Step Function - dynamodb query with Boolean Filter

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