I’m reading about DynamoDB transactions and it says:

You can’t target the same item with multiple operations within the same transaction. For example, you can’t perform a ConditionCheck and also an Update action on the same item in the same transaction.

However, when you go to the DynamoDB transaction examples, I see:

Update markItemSold = new Update()
    .withTableName(PRODUCT_TABLE_NAME)
    .withKey(productItemKey)
    .withUpdateExpression("SET ProductStatus = :new_status")
    .withExpressionAttributeValues(expressionAttributeValues)
    .withConditionExpression("ProductStatus = :expected_status")
    .withReturnValuesOnConditionCheckFailure(ReturnValuesOnConditionCheckFailure.ALL_OLD);

So which is it? Is it that case that “you can’t perform a ConditionCheck and also an Update action on the same item in the same transaction” or not?