Error: DynamoDB Duplicate Key Error

Answered by Rafal Wilinski
What's Causing This Error
As the name suggests, the duplicate key error in DynamoDB arises when you try to insert an item on an existing primary key in the same table. In this case, the new item will overwrite the existing item with the new values. So, you can configure it in such a way that prevents the data from being overwritten.
Solution: Here's How To Resolve It
Using a conditional put operation is the easiest method to protect your data from being overwritten. By doing so, you can ensure a new entry is added only if the primary key does not exist. Here, set the Exists
to false
for the primary key attributes. That prevents the data from being overwritten if the key already exists. It is essential to check whether the primary key value is unique before inserting an item.
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