Manage Partitions

This guide walks you through how to create and manage partitions in a collection.

Overview

A partition on Zilliz Cloud represents a sub-division of a collection. This functionality allows the physical storage of a collection to be divided into multiple parts, contributing to improved query performance by narrowing down the focus to a smaller subset of data rather than the entire collection.

Upon the creation of a collection, at least a default partition named _default is automatically created. You can create a maximum of 4,096 partitions within a collection.

For a comprehensive understanding of the relationships between clusters, collections, indexes, partitions, and entities, read Cluster, Collection & Entities.

📘Notes

Zilliz Cloud introduces a feature called Partition Key, leveraging the underlying partitions to store entities based on the hashed values of a specific field. This feature facilitates the implementation of multi-tenancy, enhancing search performance. For details, read Use Partition Key.

If the Partition Key feature is on in a collection, Zilliz Cloud takes care of managing all the partitions, relieving you of this responsibility.

Preparations

The code snippet below repurposes the existing code to establish a connection to a Zilliz Cloud cluster and create a collection in a quick-setup mode, indicating that the collection is loaded upon creation.

Python

from pymilvus import MilvusClient, DataType

CLUSTER_ENDPOINT = "YOUR_CLUSTER_ENDPOINT"
TOKEN = "YOUR_CLUSTER_TOKEN"

# 1. Set up a Milvus client
client = MilvusClient(
    uri=CLUSTER_ENDPOINT,
    token=TOKEN 
)

# 2. Create a collection
client.create_collection(
    collection_name="quick_setup",
    dimension=5,
)

Java

import io.milvus.v2.client.ConnectConfig;
import io.milvus.v2.client.MilvusClientV2;
import io.milvus.v2.service.collection.request.CreateCollectionReq;

String CLUSTER_ENDPOINT = "YOUR_CLUSTER_ENDPOINT";
String TOKEN = "YOUR_CLUSTER_TOKEN";

// 1. Connect to Milvus server
ConnectConfig connectConfig = ConnectConfig.builder()
    .uri(CLUSTER_ENDPOINT)
    .token(TOKEN)
    .build();

MilvusClientV2 client = new MilvusClientV2(connectConfig);

// 2. Create a collection in quick setup mode
CreateCollectionReq quickSetupReq = CreateCollectionReq.builder()
    .collectionName("quick_setup")
    .dimension(5)
    .build();

client.createCollection(quickSetupReq);

NodeJS

const address = "YOUR_CLUSTER_ENDPOINT"
const token = "YOUR_CLUSTER_TOKEN"

// 1. Set up a Milvus Client
client = new MilvusClient({address, token});

// 2. Create a collection in quick setup mode
await client.createCollection({
    collection_name: "quick_setup",
    dimension: 5,
});  

📘Notes

In the above code snippet, the index of the collection has been created along with the collection, indicating that the collection is loaded upon creation.

List Partitions

Once a collection is ready, you can list its partitions.

Python

# 3. List partitions
res = client.list_partitions(collection_name="quick_setup")
print(res)

# Output
#
# ["_default"]

Java

import io.milvus.v2.service.partition.request.ListPartitionsReq;

// 3. List all partitions in the collection
ListPartitionsReq listPartitionsReq = ListPartitionsReq.builder()
    .collectionName("quick_setup")
    .build();

List<String> partitionNames = client.listPartitions(listPartitionsReq);

System.out.println(partitionNames);

// Output:
// ["_default"]

NodeJS

// 3. List partitions
res = await client.listPartitions({
    collection_name: "quick_setup"
})

console.log(res.partition_names)

// Output
// 
// [ '_default' ]
// 

The output of the above code snippet includes the names of the partitions within the specified collection.

📘Notes

If you have set a field as the partition key in a collection, Zilliz Cloud creates at least 64 partitions along with the collection. When listing the partitions, the results may differ from the output of the above code snippets.

For details, refer to Use Partition Key.

Create Partitions

You can add more partitions to the collection. A collection can have up to 64 partitions.

Python

# 4. Create more partitions
client.create_partition(
    collection_name="quick_setup",
    partition_name="partitionA"
)

client.create_partition(
    collection_name="quick_setup",
    partition_name="partitionB"
)

res = client.list_partitions(collection_name="quick_setup")
print(res)

# Output
#
# ["_default", "partitionA", "partitionB"]

Java

import io.milvus.v2.service.partition.request.CreatePartitionReq;

// 4. Create more partitions
CreatePartitionReq createPartitionReq = CreatePartitionReq.builder()
    .collectionName("quick_setup")
    .partitionName("partitionA")
    .build();

client.createPartition(createPartitionReq);

createPartitionReq = CreatePartitionReq.builder()
    .collectionName("quick_setup")
    .partitionName("partitionB")
    .build();

client.createPartition(createPartitionReq);

listPartitionsReq = ListPartitionsReq.builder()
    .collectionName("quick_setup")
    .build();

partitionNames = client.listPartitions(listPartitionsReq);

System.out.println(partitionNames);

// Output:
// [
//     "_default",
//     "partitionA",
//     "partitionB"
// ]

NodeJS

// 4. Create more partitions
await client.createPartition({
    collection_name: "quick_setup",
    partition_name: "partitionA"
})

await client.createPartition({
    collection_name: "quick_setup",
    partition_name: "partitionB"
})

res = await client.listPartitions({
    collection_name: "quick_setup"
})

console.log(res.partition_names)

// Output
// 
// [ '_default', 'partitionA', 'partitionB' ]
// 

The code snippet above creates a partition in a collection and lists the partitions of the collection.

📘Notes

If you have set a field as the partition key in a collection, Zilliz Cloud takes care of managing the partitions in the collection. Therefore, you may encounter prompted errors when attempting to create partitions.

For details, refer to Use Partition Key.

Check for a Specific Partition

You can also check the existence of a specific partition.

Python

# 5. Check whether a partition exists
res = client.has_partition(
    collection_name="quick_setup",
    partition_name="partitionA"
)
print(res)

# Output
#
# True

res = client.has_partition(
    collection_name="quick_setup",
    partition_name="partitionC"
)
print(res)

# Output
#
# False

Java

import io.milvus.v2.service.partition.request.HasPartitionReq;

// 5. Check whether a partition exists
HasPartitionReq hasPartitionReq = HasPartitionReq.builder()
    .collectionName("quick_setup")
    .partitionName("partitionA")
    .build();

boolean exists = client.hasPartition(hasPartitionReq);

System.out.println(exists);

// Output:
// true

hasPartitionReq = HasPartitionReq.builder()
    .collectionName("quick_setup")
    .partitionName("partitionC")
    .build();

exists = client.hasPartition(hasPartitionReq);

System.out.println(exists);

// Output:
// false

NodeJS

// 5. Check whether a partition exists
res = await client.hasPartition({
    collection_name: "quick_setup",
    partition_name: "partitionA"
})

console.log(res.value)

// Output
// 
// true
// 

res = await client.hasPartition({
    collection_name: "quick_setup",
    partition_name: "partitionC"
})

console.log(res.value)

// Output
// 
// false
// 

The code snippet above checks whether the collection has a partition named partitionA and partitionC.

Load & Release Partitions

You can load and release specific partitions to make them available or unavailable for searches and queries.

Get Load Status

To check the load status of a collection and its partitions, do as follows:

Python

# 6. Load a partition independantly
client.release_collection(collection_name="quick_setup")

res = client.get_load_state(collection_name="quick_setup")
print(res)

# Output
#
# {
#     "state": "<LoadState: NotLoad>"
# }

client.load_partitions(
    collection_name="quick_setup",
    partition_names=["partitionA"]
)

res = client.get_load_state(collection_name="quick_setup")
print(res)

# Output
#
# {
#     "state": "<LoadState: Loaded>"
# }

res = client.get_load_state(collection_name="quick_setup", partition_name="partitionA")
print(res)

# Output
#
# {
#     "state": "<LoadState: Loaded>"
# }

res = client.get_load_state(collection_name="quick_setup", partition_name="partitionB")
print(res)

# Output
#
# {
#     "state": "<LoadState: NotLoad>"
# }

Java

import io.milvus.v2.service.collection.request.GetLoadStateReq;
import io.milvus.v2.service.collection.request.ReleaseCollectionReq;
import io.milvus.v2.service.partition.request.LoadPartitionsReq;
import io.milvus.v2.service.partition.request.ReleasePartitionsReq;

// 6. Load a partition independantly
// 6.1 Release the collection
ReleaseCollectionReq releaseCollectionReq = ReleaseCollectionReq.builder()
    .collectionName("quick_setup")
    .build();

client.releaseCollection(releaseCollectionReq);

// 6.2 Load partitionA
LoadPartitionsReq loadPartitionsReq = LoadPartitionsReq.builder()
    .collectionName("quick_setup")
    .partitionNames(List.of("partitionA"))
    .build();

client.loadPartitions(loadPartitionsReq);

Thread.sleep(3000);

// 6.3 Check the load status of the collection and its partitions
GetLoadStateReq getLoadStateReq = GetLoadStateReq.builder()
    .collectionName("quick_setup")
    .build();

boolean state = client.getLoadState(getLoadStateReq);

System.out.println(state);

// Output:
// true

getLoadStateReq = GetLoadStateReq.builder()
    .collectionName("quick_setup")
    .partitionName("partitionA")
    .build();

state = client.getLoadState(getLoadStateReq);

System.out.println(state);

// Output:
// true

getLoadStateReq = GetLoadStateReq.builder()
    .collectionName("quick_setup")
    .partitionName("partitionB")
    .build();

state = client.getLoadState(getLoadStateReq);

System.out.println(state);

// Output:
// false

NodeJS

// 6. Load a partition indenpendantly
await client.releaseCollection({
    collection_name: "quick_setup"
})

res = await client.getLoadState({
    collection_name: "quick_setup"
})

console.log(res.state)

// Output
// 
// LoadStateNotLoad
// 

await client.loadPartitions({
    collection_name: "quick_setup",
    partition_names: ["partitionA"]
})

await sleep(3000)

res = await client.getLoadState({
    collection_name: "quick_setup"
})

console.log(res.state)

// Output
// 
// LoadStateLoaded
// 

res = await client.getLoadState({
    collection_name: "quick_setup",
    partition_name: "partitionA"
})

console.log(res.state)

// Output
// 
// LoadStateLoaded
// 

res = await client.getLoadState({
    collection_name: "quick_setup",
    partition_name: "partitionB"
})

console.log(res.state)

// Output
// 
// LoadStateLoaded
// 

Possible load status may be either of the following

📘Notes

In Java SDK, the result is a boolean value indicating whether the partition has been loaded or not.

• Loaded

  A collection is marked as Loaded if at least one of its partitions has been loaded.

• Not Loaded

  A collection is marked as NotLoad if none of its partitions has been loaded.

• Loading

  A collection is marked as Loading if at least one of its partitions is in the loading process.

Load Partitions

To load all partitions of a collection, you can just call load_collection(). To load specific partitions of a collection, do as follows:

Python

client.load_partitions(
    collection_name="quick_setup",
    partition_names=["partitionA"]
)

res = client.get_load_state(collection_name="quick_setup")
print(res)

# Output
#
# {
#     "state": "<LoadState: Loaded>"
# }

Java

LoadPartitionsReq loadPartitionsReq = LoadPartitionsReq.builder()
    .collectionName("quick_setup")
    .partitionNames(List.of("partitionA"))
    .build();

client.loadPartitions(loadPartitionsReq);

getLoadStateReq = GetLoadStateReq.builder()
    .collectionName("quick_setup")
    .partitionName("partitionA")
    .build();

state = client.getLoadState(getLoadStateReq);

System.out.println(state);

// Output:
// true

NodeJS

await client.loadPartitions({
    collection_name: "quick_setup",
    partition_names: ["partitionA"]
})

res = await client.getLoadState({
    collection_name: "quick_setup",
    partition_name: "partitionA"
})

console.log(res.state)

// Output
// 
// LoadStateLoaded
//

To load multiple partitions at a time, do as follows:

Python

client.load_partitions(
    collection_name="quick_setup",
    partition_names=["partitionA", "partitionB"]
)

res = client.get_load_status(
    collection_name="quick_setup",
    partition_name="partitionA"
)

# Output
#
# {
#     "state": "<LoadState: Loaded>"
# }

res = client.get_load_status(
    collection_name="quick_setup",
    partition_name="partitionB"
)

# Output
#
# {
#     "state": "<LoadState: Loaded>"
# }

Java

LoadPartitionsReq loadPartitionsReq = LoadPartitionsReq.builder()
    .collectionName("quick_setup")
    .partitionNames(List.of("partitionA", "partitionB"))
    .build();

client.loadPartitions(loadPartitionsReq);

getLoadStateReq = GetLoadStateReq.builder()
    .collectionName("quick_setup")
    .partitionName("partitionA")
    .build();

state = client.getLoadState(getLoadStateReq);

System.out.println(state);

// Output:
// true

getLoadStateReq = GetLoadStateReq.builder()
    .collectionName("quick_setup")
    .partitionName("partitionB")
    .build();

state = client.getLoadState(getLoadStateReq);

System.out.println(state);

// Output:
// true

NodeJS

await client.loadPartitions({
    collection_name: "quick_setup",
    partition_names: ["partitionA", "partitionB"]
})

res = await client.getLoadState({
    collection_name: "quick_setup",
    partition_name: "partitionA"
})

console.log(res)

// Output
// 
// LoadStateLoaded
// 

res = await client.getLoadState({
    collection_name: "quick_setup",
    partition_name: "partitionB"
})

console.log(res)

// Output
// 
// LoadStateLoaded
// 

Release Partitions

To release all partitions of a collection, you can just call release_collection. To release specific partitions of a collection, do as follows:

Python

# 7. Release a partition
client.release_partitions(
    collection_name="quick_setup",
    partition_names=["partitionA"]
)

res = client.get_load_state(collection_name="quick_setup", partition_name="partitionA")
print(res)

# Output
#
# {
#     "state": "<LoadState: NotLoad>"
# }

Java

import io.milvus.v2.service.partition.request.ReleasePartitionsReq;

// 7. Release a partition
ReleasePartitionsReq releasePartitionsReq = ReleasePartitionsReq.builder()
    .collectionName("quick_setup")
    .partitionNames(List.of("partitionA"))
    .build();

client.releasePartitions(releasePartitionsReq);

getLoadStateReq = GetLoadStateReq.builder()
    .collectionName("quick_setup")
    .partitionName("partitionA")
    .build();

state = client.getLoadState(getLoadStateReq);

System.out.println(state);

// Output:
// false

NodeJS

// 7. Release a partition
await client.releasePartitions({
    collection_name: "quick_setup",
    partition_names: ["partitionA"]
})

res = await client.getLoadState({
    collection_name: "quick_setup"
})

console.log(res.state)

// Output
// 
// LoadStateNotLoad
// 

To release multiple or all partitions at a time, do as follows:

Python

client.release_partitions(
    collection_name="quick_setup",
    partition_names=["_default", "partitionA", "partitionB"]
)

res = client.get_load_status(
    collection_name="quick_setup",
)

# Output
#
# {
#     "state": "<LoadState: NotLoad>"
# }

Java

import io.milvus.v2.service.partition.request.ReleasePartitionsReq;

ReleasePartitionsReq releasePartitionsReq = ReleasePartitionsReq.builder()
    .collectionName("quick_setup")
    .partitionNames(List.of("_default", "partitionA", "partitionB"))
    .build();

client.releasePartitions(releasePartitionsReq);

getLoadStateReq = GetLoadStateReq.builder()
    .collectionName("quick_setup")
    .build();

state = client.getLoadState(getLoadStateReq);

System.out.println(state);

// Output:
// false

NodeJS

await client.releasePartitions({
    collection_name: "quick_setup",
    partition_names: ["_default", "partitionA", "partitionB"]
})

res = await client.getLoadState({
    collection_name: "quick_setup"
})

console.log(res)

// Output
// 
// {
//   status: {
//     error_code: 'Success',
//     reason: '',
//     code: 0,
//     retriable: false,
//     detail: ''
//   },
//   state: 'LoadStateNotLoad'
// }
// 

Drop Partitions

Once you release a partition, you can drop it if it is no longer needed.

Python

# 8. Drop a partition
client.drop_partition(
    collection_name="quick_setup",
    partition_name="partitionB"
)

res = client.list_partitions(collection_name="quick_setup")
print(res)

# Output
#
# ["_default", "partitionA"]

Java

// 8. Drop a partition
DropPartitionReq dropPartitionReq = DropPartitionReq.builder()
    .collectionName("quick_setup")
    .partitionName("partitionB")
    .build();

client.dropPartition(dropPartitionReq);

listPartitionsReq = ListPartitionsReq.builder()
    .collectionName("quick_setup")
    .build();

partitionNames = client.listPartitions(listPartitionsReq);

System.out.println(partitionNames);

// Output:
// [
//     "_default",
//     "partitionA"
// ]

NodeJS

// 8 Drop a partition
await client.dropPartition({
    collection_name: "quick_setup",
    partition_name: "partitionB"
})

res = await client.listPartitions({
    collection_name: "quick_setup"
})

console.log(res.partition_names)

// Output
// 
// [ '_default', 'partitionA' ]
// 

📘Notes

Before dropping a partition, you need to release it from memory.