Check Collection Information

This topic describes how to check the information of the collection in Milvus.

Check if a collection exists

Verify if a collection exists in Milvus.

from pymilvus import utility
utility.has_collection("book")

await milvusClient.collectionManager.hasCollection({
  collection_name: "book",
});

hasColl, err := milvusClient.HasCollection(
    context.Background(), // ctx
    collectionName,       // CollectionName
)
if err != nil {
    log.Fatal("failed to check whether collection exists:", err.Error())
}
log.Println(hasColl)

R<Boolean> respHasCollection = milvusClient.hasCollection(
        HasCollectionParam.newBuilder()
                .withCollectionName("book")
                .build());
if (respHasCollection.getData() == Boolean.TRUE) {
    System.out.println("Collection exists.");
}

describe collection -c book

Check collection details

Check the details of a collection.

from pymilvus import Collection
collection = Collection("book")  # Get an existing collection.

collection.schema                # Return the schema.CollectionSchema of the collection.
collection.description           # Return the description of the collection.
collection.name                  # Return the name of the collection.
collection.is_empty              # Return the boolean value that indicates if the collection is empty.
collection.num_entities          # Return the number of entities in the collection.
collection.primary_field         # Return the schema.FieldSchema of the primary key field.
collection.partitions            # Return the list[Partition] object.
collection.indexes               # Return the list[Index] object.

await milvusClient.collectionManager.describeCollection({          // Return the name and schema of the collection.
  collection_name: "book",
});

await milvusClient.collectionManager.getCollectionStatistics({     // Return the statistics information of the collection.
  collection_name: "book",
});

collDesc, err := milvusClient.DescribeCollection(               // Return the name and schema of the collection.
    context.Background(),   // ctx
    "book",                 // CollectionName
)
if err != nil {
    log.Fatal("failed to check collection schema:", err.Error())
}
log.Printf("%v\n", collDesc)

collStat, err := milvusClient.GetCollectionStatistics(          // Return the statistics information of the collection.
    context.Background(),   // ctx
    "book",                 // CollectionName
)
if err != nil {
log.Fatal("failed to check collection statistics:", err.Error())
}

R<DescribeCollectionResponse> respDescribeCollection = milvusClient.describeCollection(          // Return the name and schema of the collection.
        DescribeCollectionParam.newBuilder()
                .withCollectionName("book")
                .build());
DescCollResponseWrapper wrapperDescribeCollection = new DescCollResponseWrapper(respDescribeCollection.getData());
System.out.println(wrapperDescribeCollection);

R<GetCollectionStatisticsResponse> respCollectionStatistics = milvusClient.getCollectionStatistics(   // Return the statistics information of the collection.
        GetCollectionStatisticsParam.newBuilder()
                .withCollectionName("book")
                .build());
GetCollStatResponseWrapper wrapperCollectionStatistics = new GetCollStatResponseWrapper(respCollectionStatistics.getData());
System.out.println("Collection row count: " + wrapperCollectionStatistics.getRowCount());

describe collection -c book

        <th>Description</th>
    </tr>
</thead>
<tbody>
    <tr>
        <td><code>status</code></td>
        <td>{ error_code: number, reason: string }</td>
    </tr>
    <tr>
        <td><code>schema</code></td>
        <td>Information of all fields in this collection</td>
    <tr>
        <td><code>collectionID</code></td>
        <td> collectionID</td>
    </tr>
</tbody>

List all collections

List all collections in this Milvus Instance.

from pymilvus import utility
utility.list_collections()

await milvusClient.collectionManager.showCollections();

listColl, err := milvusClient.ListCollection(
    context.Background(),   // ctx
    )
if err != nil {
		log.Fatal("failed to list all collections:", err.Error())
    }
log.Println(listColl)

R<ShowCollectionsResponse> respShowCollections = milvusClient.showCollections(
        ShowCollectionsParam.newBuilder()
                .build());
System.out.println(respShowCollections);

list collections

What's next

• Learn more basic operations of Milvus:
  • Insert data into Milvus
  • Create a partition
  • Build an index for vectors
  • Conduct a vector search
  • Conduct a hybrid search
• Explore API references for Milvus SDKs:
  • PyMilvus API reference
  • Node.js API reference