Error: comparison operator does not return all attributes dynamodb

What's Causing This Error

This error may occur due to several reasons.

1. Firstly, only the items that match the specified Key Condition Expression will get returned from the DynamoDB table.
2. Secondly, if you are querying an index that does not project the required attribute, it will not appear in the response.
3. Finally, if your query uses any Projection Attributes, DyanamoDB will only return the specified attributes in the response.

Solution: Here's How To Resolve It

There is no definite way of fixing this error. However, you can try any solution from the following to see which works for you.

If Querying an Index

If you are querying a Local or Global Secondary Index, ensure that the attributes you need are projected onto it. Then, you can configure the projection attributes when you create the index.

If Querying with no index

If you are querying data directly from the table, ensure that the item has the required attributes. Since DynamoDB is schema-less, items can contain different attributes.

Secondly, if you are using a ProjectionExpression, ensure that the attributes you need are projected in the query, as DynamoDB will only fetch the projected attributes. You can also choose to get all the attributes by omitting the projection expression.