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When a Data Source or Datamart has not previously been deployed, i.e., there is no corresponding table in the database, then a distributed table is created for it on the first deploy. In new implementations, it is recommended to choose the distribution key and configure it in the necessary Data Sources and Datamarts from the beginning.
Distribution Key Requirements
Key Field Designation – The distribution key should be a key field of the DS/DM. Typically, either the product ID or customer ID field is chosen as the distribution key.
Consistency Across DS and DM – To maximize performance, the field used as the distribution key in the DM must also be defined as the distribution key in the DS from which it is sourced.
Recommendation for Product DS – Unless the Product DS is very small, it is recommended to define the productId key field as a distribution key. This ensures optimal performance during data loading and querying.
Existing Data Sources / Datamarts
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