change-pk-nosql

Author: richagaur

articles/cosmos-db/nosql/change-pk.md

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+---
+title: Change Partition Key
+titleSuffix: Azure Cosmos DB
+description: Change partition key in Azure Cosmos DB for NOSQL API.
+author: richagaur
+ms.author: richagaur
+ms.service: cosmos-db
+ms.topic: conceptual
+---
+# Changing the Partition Key in Azure Cosmos DB (Preview)
+
+[!INCLUDE[NoSQL](includes/appliesto-nosql.md)]
+
+In the realm of database management, it is not uncommon for the initially chosen partition key for a container to become inadequate as applications evolve. This can result in suboptimal performance and increased costs for the container. Several factors contributing to this situation include:
+
+- [Cross partition queries](https://learn.microsoft.com/azure/cosmos-db/nosql/how-to-query-container#avoid-cross-partition-queries)
+- [Hot partitions](https://learn.microsoft.com/azure/cosmos-db/nosql/troubleshoot-request-rate-too-large?tabs=resource-specific#how-to-identify-the-hot-partition)
+
+To address these issues, Azure Cosmos DB offers the ability to seamlessly change the partition key using the Azure Portal.
+
+## Getting Started
+
+To change the partition key of a container in Azure Cosmos DB for the NoSQL API using the Azure Portal, follow these steps:
+
+1. Navigate to the **Data Explorer** in the Azure Cosmos DB portal and select the container for which you need to change the partition key.
+2. Proceed to the **Scale & Settings** option and choose the **Partition Keys** tab.
+3. Select the **Change** button to initiate the partition key change process.
+
+![Screenshot of the Change partition key feature in the Data Explorer in an Azure Cosmos DB account.](media/change-pk/cosmosdb-change-pk.png)
+
+## How the Change Partition Key Works
+
+Changing the partition key entails creating a new destination container or selecting an existing destination container within the same database.
+
+If creating a new container using the Azure portal while changing the partition key, all configurations except for the partition key and unique keys are replicated to the destination container.
+
+![Screenshot of create or select destination container screen while changing partition key in an Azure Cosmos DB account.](media/change-pk/cosmosdb-change-pk-create-container.png)
+
+Subsequently, data is copied from the source container to the destination container in an offline manner utilizing the [Intra-account container copy](https://learn.microsoft.com/azure/cosmos-db/container-copy#how-does-container-copy-work) job.
+
+>[!Note]
+> It is recommended to stop all updates on the source container before proceeding to change the partition key of the container for entire duration of copy process to maintain data integrity.
+
+Once the copy is complete, you can start using the new container with desired partition key and optionally delete the old container.
+
+## Next Steps
+
+- Explore more about [container copy jobs](https://learn.microsoft.com/azure/cosmos-db/container-copy).
+- Learn further about [how to choose a partition key](https://learn.microsoft.com/azure/cosmos-db/partitioning-overview#choose-partitionkey).