Error: accessdeniedexception dynamodb

What's Causing This Error

You may encounter this error if the service trying to access a DynamoDB resource does not have the required permissions. For example, if a Lambda function does not have the DynamoDB policy attached to its IAM role, the Lambda function will not be able to access any DynamoDB resource.

Solution - Here's How To Resolve It

To resolve the error, attach the required policy (use an AWS-managed or customer-managed policy) to the IAM role assigned to the service.

For example, you can add the IAM Policy statement below to allow a Lambda function to perform only the "query" and "update" operations for all tables. Without adding this policy, the Lambda function cannot access any DynamoDB resource (default nature).

{
  "Version": "2012-10-17",
  "Statement": [
      {
          "Effect": "Allow",
          "Action": [
              "dynamodb:Query",
              "dynamodb:UpdateItem"
          ],
          "Resource": "*"
      }
  ]
}