describeCollection()
A MilvusClient interface. This method shows the details of a collection, e.g. name, schema.
R<DescribeCollectionResponse> describeCollection(DescribeCollectionParam requestParam);
DescribeCollectionParam
Use the DescribeCollectionParam.Builder
to construct a DescribeCollectionParam
object.
import io.milvus.param.DescribeCollectionParam;
DescribeCollectionParam.Builder builder = DescribeCollectionParam.newBuilder();
Methods of DescribeCollectionParam.Builder
:
Method | Description | Parameters |
---|---|---|
withCollectionName(String collectionName) | Sets the collection name. Collection name cannot be empty or null. | collectionName: The name of the collection to release. |
withDatabaseName(String databaseName) | Sets the database name. database name can be null for default database. | databaseName: The database name. |
build() | Constructs a ReleaseCollectionParam object. | N/A |
The DescribeCollectionParam.Builder.build()
can throw the following exceptions:
- ParamException: error if the parameter is invalid.
Returns
This method catches all the exceptions and returns an R<DescribeCollectionResponse>
object.
-
If the API fails on the server side, it returns the error code and message from the server.
-
If the API fails by RPC exception, it returns
R.Status.Unknown
and the error message of the exception. -
If the API succeeds, it returns a valid
DescribeCollectionResponse
held by theR
template. You can useDescCollResponseWrapper
to get the information.
DescCollResponseWrapper
A tool class to encapsulate the DescribeCollectionResponse.
import io.milvus.response.DescCollResponseWrapper;
DescCollResponseWrapper wrapper = new DescCollResponseWrapper(response);
Methods of DescCollResponseWrapper
:
Method | Description | Parameters | Returns |
---|---|---|---|
getCollectionName() | Get the name of the collection. | N/A | String |
getCollectionDescription() | Get the description of the collection. | N/A | String |
getCollectionID() | Get the internal ID of the collection. | N/A | long |
getShardNumber() | Get the shard number of the collection. | N/A | int |
getCreatedUtcTimestamp() | Get UTC timestamp when the collection is created. | N/A | long |
getAliases() | Get aliases of the collection. | N/A | List<String> |
getFields() | Get the schema of the collection's fields. | N/A | List<FieldType> |
getFieldByName(String fieldName) | Get the schema of a field by name.Return null if the field doesn't exist. | fieldName: The name of a field | FieldType |
isDynamicFieldEnabled() | Get whether the collection dynamic field is enabled | N/A | boolean |
getPartitionKeyField() | Get the partition key field.Return null if the partition key field doesn't exist. | N/A | FieldType |
Example
import io.milvus.param.*;
import io.milvus.response.DescCollResponseWrapper;
DescribeCollectionParam param = DescribeCollectionParam.newBuilder()
.withCollectionName(COLLECTION_NAME)
.build();
R<DescribeCollectionResponse> response = client.describeCollection(param);
if (response.getStatus() != R.Status.Success.getCode()) {
System.out.println(response.getMessage());
}
DescCollResponseWrapper wrapper = new DescCollResponseWrapper(response.getData());
System.out.println("Shard number: " + wrapper.getShardNumber());