BoostRanker

The BoostRanker extends from the Function class and provides extra parameters.

public class BoostRanker extends CreateCollectionReq.Function

Request Syntax

BoostRanker.builder()
    .name(String name)
    .description(String description)
    .inputFieldNames(List<String> inputFieldNames)
    .params(Map<String, String> params)
    .filter(String filter)
    .weight(Float weight)
    .randomScoreSeed(Long randomScoreSeed)
    .randomScoreField(String randomScoreField)
    .build()

BUILDER METHODS:

• name(String name)

  The name of the function. This identifier is used to reference the function within queries and collections.

• description(String description)

  A brief description of the function’s purpose. This can be useful for documentation or clarity in larger projects and defaults to an empty string.

• inputFieldNames(List<String> inputFieldNames)

  The name of the field containing the raw data that requires conversion to vector representation. For functions using FunctionType.RERANK, this parameter accepts only one field name.

• params(Map<String, String> params)

  A set of key-value pairs that configures the function properties.

• filter(String filter)

  The filter expression that will be used to match entities among search result entities. It can be any valid basic filter expression mentioned in Filtering Explained.

  notes

  Only use basic operators, such as ==, >, or <. Using advanced operators, such as text_match or phrase_match, will degrade search performance.

• weight(Float weight)

  The weight that will be multiplied by the scores of any matching entities in the raw search results.

  The value should be a floating-point number.

  • To emphasize the importance of matching entities, set it to a value that boosts the scores.

  • To demote matching entities, assign this parameter a value that lowers their scores.

• randomScoreSeed(Long randomScoreSeed)

  The random function that works with randomScoreField(String randomScoreField) to generate a value between 0 and 1 randomly.

  You should specify an initial value to start a pseudorandom number generator (PRNG).

• randomScoreField(String randomScoreField)

  The random function that works with randomScoreSeed(Long randomScoreSeed) to generate a value between 0 and 1 randomly.

  You should specify the name of a field whose value will be used as a random factor in generating the random number. A field with unique values will suffice.

RETURN TYPE:

BoostRanker

RETURNS:

A boost ranker instance.

Examples:

import io.milvus.v2.service.collection.request.CreateCollectionReq.Function;
import io.milvus.v2.service.vector.request.ranker.BoostRanker
import java.util.Collections;

// use the ModelRanker class
BoostRanker boost = BoostRanker.builder()
    .name("xxx_boost")
    .description("boost on xxx")
    .filter("xxx == 2")
    .weight(0.5)
    .randomScoreSeed(123)
    .randomScoreField("id")
    .build()
    
// Instead, you can use the Function class as well
CreateCollectionReq.Function boost = CreateCollectionReq.Function.builder()
    .functionType(FunctionType.RERANK)
    .name("xxx_boost")
    .description("boost on xxx")
    .param("reranker", "boost")
    .param("filter", "xxx == 2")
    .param("weight", "0.5")
    .param("random_score", "{\"seed\": 123, \"field\": \"id\"}")
    .build();