DynamoDB Update Item

Hi Guys, I am new to Knime and I was trying to update a Table in Amazon DynamoDB using the “Amazon DynamoDb Update Item” looking for some examples as to how to fill in the Condition Expression I want to update records that matches my primary key.
What should go in the update express and the name mapping and Value Mapping. Any examples would be greatly appreciated.

Hi @reevesedward,

Welcome to the Forum!

Here is an example of how you can populate these fields:

  1. Update Expression: Defines the update, e.g., SET attributename = :value.
  2. Condition Expression: To make sure updates only if conditions are met, e.g., attribute_exists(primaryKey).
  3. Name Mapping: Maps placeholder names to attribute names, e.g., { "#attrName": "attributeName" }.
  4. Value Mapping: Defines the values used in expressions, e.g., { ":value": { "S": "newvalue" } }.

For more details, check the options tab of the node in KNIME:

Also the update expression and the condition expression links from the Amazon documents are mentioned on the node page.

Hope this helps.


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