milvus-logo

delete()

A MilvusClient interface. This method deletes an entity or entities from a collection by filtering the primary key field with boolean expression.

R<MutationResult> delete(DeleteParam requestParam);

DeleteParam

Use the DeleteParam.Builder to construct a DeleteParam object.

import io.milvus.param.DeleteParam;
DeleteParam.Builder builder = DeleteParam.newBuilder();

Methods of DeleteParam.Builder:

MethodDescriptionParameters
withCollectionName(String collectionName)Sets the collection name. The collection name cannot be empty or null.collectionName: The name of the collection to delete the entity or entities from.
withPartitionName(String partitionName)Sets the target partition name (Optional).partitionName: The name of the partition to delete the entity or entities from.
withExpr(String expr)Sets the expression filtering to pick out the entities to be deleted. Currently, only expression in the format of "pk_field in [1, 2, ...]" is supported.expr: The expression used for filtering the primary key field.
build()Constructs a DeleteParam object.N/A

The DeleteParam.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<MutationResult> 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.Unknow and the error message of the exception.

  • If the API succeeds, it returns a valid MutationResult held by the R template. You can use MutationResultWrapper to get the returned information. See the corresponding section in insert() for more information about MutationResultWrapper.

Example

import io.milvus.param.*;
import io.milvus.grpc.MutationResult;

DeleteParam param = DeleteParam.newBuilder()
        .withCollectionName(collectionName)
        .withPartitionName(partitionName)
        .withExpr("id in [100, 200, 300]")
        .build();
R<MutationResult> response = milvusClient.delete(param);
if (response.getStatus() != R.Status.Success.getCode()) {
    System.out.println(response.getMessage());
}