{"id":"dynamodb-putitem-prevent-overwrite-condition","text":"PutItem can prevent overwrites using `ConditionExpression: \"attribute_not_exists(<partition_key>)\"` to insert only if the item doesn't already exist.","truth_value":"IN","source":"entries/2026/03/11/amazondynamodb-latest-APIReference-API_PutItemhtml.md","source_url":"","source_hash":"bb016de9e0628e59","justifications":[],"dependents":[],"metadata":{},"explanation":{"steps":[{"node":"dynamodb-putitem-prevent-overwrite-condition","truth_value":"IN","reason":"premise"}]}}