@JohnPaulRaja,C In Pega Platform, queue processors do not have a built-in option to set a partition key to ensure message order. However, you can consider using a custom solution to achieve this. One approach is to create multiple dedicated queue processors, each handling a specific partition key. You can then route messages to the appropriate queue processor based on the partition key. This way, messages with the same partition key will be processed in order by the same queue processor. Keep in mind that this custom solution may require additional configuration and maintenance.

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Passing parameters into dedicated queue processor

Queue-For-Processing method > Parameters { .section}

Understanding queue processors > Standard queue processing

Processing large amount of data using Queue Processor