跳到主要内容

Nullable 和 Default

Milvus 允许您为标量字段(主字段除外)设置 nullable 属性和默认值。对于标记为 nullable=True 的字段,您可以在插入数据时跳过该字段,或直接将其设置为 null 值,系统会将其视为 null 而不会导致错误。当字段具有默认值时,如果在插入过程中没有为该字段指定数据,系统将自动应用此值。

默认值和 nullable 属性通过允许处理具有 null 值的数据集并保留默认值设置,简化了从其他数据库系统到 Milvus 的数据迁移。在创建 collection 时,您还可以为值可能不确定的字段启用 nullable 或设置默认值。

限制

  • 只有标量字段(不包括主字段)支持默认值和 nullable 属性。

  • JSON 和 Array 字段不支持默认值。

  • 默认值或 nullable 属性只能在创建 collection 时配置,之后无法修改。

  • 启用了 nullable 属性的标量字段不能在分组搜索中用作 group_by_field。有关分组搜索的更多信息,请参阅分组搜索

  • 标记为 nullable 的字段不能用作 partition key。有关 partition key 的更多信息,请参阅使用 Partition Key

  • 在启用了 nullable 属性的标量字段上创建索引时,null 值将被排除在索引之外。

  • JSON 和 ARRAY 字段:当使用 IS NULLIS NOT NULL 操作符过滤 JSON 或 ARRAY 字段时,这些操作符在列级别工作,这表明它们只评估整个 JSON 对象或数组是否为 null。例如,如果 JSON 对象内的键为 null,IS NULL 过滤器不会识别它。有关更多信息,请参阅基本操作符

Nullable 属性

nullable 属性允许您在 collection 中存储 null 值,在处理未知数据时提供灵活性。

设置 nullable 属性

在创建 collection 时,使用 nullable=True 定义可空字段(默认为 False)。以下示例创建一个名为 my_collection 的 collection 并将 age 字段设置为可空:

from pymilvus import MilvusClient, DataType

client = MilvusClient(uri='http://localhost:19530')

# Define collection schema
schema = client.create_schema(
auto_id=False,
enable_dynamic_schema=True,
)

schema.add_field(field_name="id", datatype=DataType.INT64, is_primary=True)
schema.add_field(field_name="vector", datatype=DataType.FLOAT_VECTOR, dim=5)
schema.add_field(field_name="age", datatype=DataType.INT64, nullable=True) # Nullable field

# Set index params
index_params = client.prepare_index_params()
index_params.add_index(field_name="vector", index_type="AUTOINDEX", metric_type="L2")

# Create collection
client.create_collection(collection_name="my_collection", schema=schema, index_params=index_params)
import io.milvus.v2.client.ConnectConfig;
import io.milvus.v2.client.MilvusClientV2;
import io.milvus.v2.common.DataType;
import io.milvus.v2.common.IndexParam;
import io.milvus.v2.service.collection.request.AddFieldReq;
import io.milvus.v2.service.collection.request.CreateCollectionReq;

import java.util.*;

MilvusClientV2 client = new MilvusClientV2(ConnectConfig.builder()
.uri("http://localhost:19530")
.build());

CreateCollectionReq.CollectionSchema schema = client.createSchema();
schema.setEnableDynamicField(true);

schema.addField(AddFieldReq.builder()
.fieldName("id")
.dataType(DataType.Int64)
.isPrimaryKey(true)
.build());

schema.addField(AddFieldReq.builder()
.fieldName("vector")
.dataType(DataType.FloatVector)
.dimension(5)
.build());

schema.addField(AddFieldReq.builder()
.fieldName("age")
.dataType(DataType.Int64)
.isNullable(true)
.build());

List<IndexParam> indexes = new ArrayList<>();
Map<String,Object> extraParams = new HashMap<>();

indexes.add(IndexParam.builder()
.fieldName("vector")
.indexType(IndexParam.IndexType.AUTOINDEX)
.metricType(IndexParam.MetricType.L2)
.build());

CreateCollectionReq requestCreate = CreateCollectionReq.builder()
.collectionName("my_collection")
.collectionSchema(schema)
.indexParams(indexes)
.build();
client.createCollection(requestCreate);
import { MilvusClient, DataType } from "@zilliz/milvus2-sdk-node";

const client = new MilvusClient({
address: "http://localhost:19530",
token: "root:Milvus",
});

await client.createCollection({
collection_name: "my_collection",
schema: [
{
name: "id",
is_primary_key: true,
data_type: DataType.int64,
},
{ name: "vector", data_type: DataType.Int64, dim: 5 },

{ name: "age", data_type: DataType.FloatVector, nullable: true },
],

index_params: [
{
index_name: "vector_inde",
field_name: "vector",
metric_type: MetricType.L2,
index_type: IndexType.AUTOINDEX,
},
],
});

import (
"context"
"fmt"

"github.com/milvus-io/milvus/client/v2/column"
"github.com/milvus-io/milvus/client/v2/entity"
"github.com/milvus-io/milvus/client/v2/index"
"github.com/milvus-io/milvus/client/v2/milvusclient"
)

ctx, cancel := context.WithCancel(context.Background())
defer cancel()

milvusAddr := "localhost:19530"

client, err := milvusclient.New(ctx, &milvusclient.ClientConfig{
Address: milvusAddr,
})
if err != nil {
fmt.Println(err.Error())
// handle error
}
defer client.Close(ctx)

schema := entity.NewSchema()
schema.WithField(entity.NewField().
WithName("id").
WithDataType(entity.FieldTypeInt64).
WithIsPrimaryKey(true),
).WithField(entity.NewField().
WithName("vector").
WithDataType(entity.FieldTypeFloatVector).
WithDim(5),
).WithField(entity.NewField().
WithName("age").
WithDataType(entity.FieldTypeInt64).
WithNullable(true),
)

indexOption := milvusclient.NewCreateIndexOption("my_collection", "vector",
index.NewAutoIndex(index.MetricType(entity.L2)))

err = client.CreateCollection(ctx,
milvusclient.NewCreateCollectionOption("my_collection", schema).
WithIndexOptions(indexOption))
if err != nil {
fmt.Println(err.Error())
// handle error
}
export pkField='{
"fieldName": "id",
"dataType": "Int64",
"isPrimary": true
}'

export vectorField='{
"fieldName": "vector",
"dataType": "FloatVector",
"elementTypeParams": {
"dim": 5
}
}'

export nullField='{
"fieldName": "age",
"dataType": "Int64",
"nullable": true
}'

export schema="{
\"autoID\": false,
\"fields\": [
$pkField,
$vectorField,
$nullField
]
}"

export indexParams='[
{
"fieldName": "vector",
"metricType": "L2",
"indexType": "AUTOINDEX"
}
]'

curl --request POST \
--url "${CLUSTER_ENDPOINT}/v2/vectordb/collections/create" \
--header "Authorization: Bearer ${TOKEN}" \
--header "Content-Type: application/json" \
-d "{
\"collectionName\": \"my_collection\",
\"schema\": $schema,
\"indexParams\": $indexParams
}"

插入实体

当您向可空字段插入数据时,插入 null 或直接省略此字段:

data = [
{"id": 1, "vector": [0.1, 0.2, 0.3, 0.4, 0.5], "age": 30},
{"id": 2, "vector": [0.2, 0.3, 0.4, 0.5, 0.6], "age": None},
{"id": 3, "vector": [0.3, 0.4, 0.5, 0.6, 0.7]}
]

client.insert(collection_name="my_collection", data=data)
import com.google.gson.Gson;
import com.google.gson.JsonObject;

import io.milvus.v2.service.vector.request.InsertReq;
import io.milvus.v2.service.vector.response.InsertResp;

List<JsonObject> rows = new ArrayList<>();
Gson gson = new Gson();
rows.add(gson.fromJson("{\"id\": 1, \"vector\": [0.1, 0.2, 0.3, 0.4, 0.5], \"age\": 30}", JsonObject.class));
rows.add(gson.fromJson("{\"id\": 2, \"vector\": [0.2, 0.3, 0.4, 0.5, 0.6], \"age\": null}", JsonObject.class));
rows.add(gson.fromJson("{\"id\": 3, \"vector\": [0.3, 0.4, 0.5, 0.6, 0.7]}", JsonObject.class));

InsertResp insertR = client.insert(InsertReq.builder()
.collectionName("my_collection")
.data(rows)
.build());
const data = [
{ id: 1, vector: [0.1, 0.2, 0.3, 0.4, 0.5], age: 30 },
{ id: 2, vector: [0.2, 0.3, 0.4, 0.5, 0.6], age: null },
{ id: 3, vector: [0.3, 0.4, 0.5, 0.6, 0.7] },
];

client.insert({
collection_name: "my_collection",
data: data,
});

column, _ := column.NewNullableColumnInt64("age",
[]int64{30},
[]bool{true, false, false})

_, err = client.Insert(ctx, milvusclient.NewColumnBasedInsertOption("my_collection").
WithInt64Column("id", []int64{1, 2, 3}).
WithFloatVectorColumn("vector", 5, [][]float32{
{0.1, 0.2, 0.3, 0.4, 0.5},
{0.2, 0.3, 0.4, 0.5, 0.6},
{0.3, 0.4, 0.5, 0.6, 0.7},
}).
WithColumns(column),
)
if err != nil {
fmt.Println(err.Error())
// handle err
}
curl --request POST \
--url "${CLUSTER_ENDPOINT}/v2/vectordb/entities/insert" \
--header "Authorization: Bearer ${TOKEN}" \
--header "Content-Type: application/json" \
-d '{
"data": [
{"id": 1, "vector": [0.1, 0.2, 0.3, 0.4, 0.5], "age": 30},
{"id": 2, "vector": [0.2, 0.3, 0.4, 0.5, 0.6], "age": null},
{"id": 3, "vector": [0.3, 0.4, 0.5, 0.6, 0.7]}
],
"collectionName": "my_collection"
}'

使用 null 值搜索和查询

当使用 search 方法时,如果字段包含 null 值,搜索结果将返回该字段为 null:

res = client.search(
collection_name="my_collection",
data=[[0.1, 0.2, 0.4, 0.3, 0.128]],
limit=2,
search_params={"params": {"nprobe": 16}},
output_fields=["id", "age"]
)

print(res)

# Output
# data: ["[{'id': 1, 'distance': 0.15838398039340973, 'entity': {'age': 30, 'id': 1}}, {'id': 2, 'distance': 0.28278401494026184, 'entity': {'age': None, 'id': 2}}]"]
import io.milvus.v2.service.vector.request.SearchReq;
import io.milvus.v2.service.vector.request.data.FloatVec;
import io.milvus.v2.service.vector.response.SearchResp;

Map<String,Object> params = new HashMap<>();
params.put("nprobe", 16);
SearchResp resp = client.search(SearchReq.builder()
.collectionName("my_collection")
.annsField("vector")
.data(Collections.singletonList(new FloatVec(new float[]{0.1f, 0.2f, 0.3f, 0.4f, 0.5f})))
.topK(2)
.searchParams(params)
.outputFields(Arrays.asList("id", "age"))
.build());

System.out.println(resp.getSearchResults());

// Output
//
// [[SearchResp.SearchResult(entity={id=1, age=30}, score=0.0, id=1), SearchResp.SearchResult(entity={id=2, age=null}, score=0.050000004, id=2)]]
client.search({
collection_name: 'my_collection',
data: [0.3, -0.6, 0.1, 0.3, 0.5],
limit: 2,
output_fields: ['age', 'id'],
params: {
nprobe: 16
}
});
queryVector := []float32{0.1, 0.2, 0.4, 0.3, 0.128}

annParam := index.NewCustomAnnParam()
annParam.WithExtraParam("nprobe", 16)
resultSets, err := client.Search(ctx, milvusclient.NewSearchOption(
"my_collection", // collectionName
2, // limit
[]entity.Vector{entity.FloatVector(queryVector)},
).WithANNSField("vector").
WithAnnParam(annParam).
WithOutputFields("id", "age"))
if err != nil {
fmt.Println(err.Error())
// handle error
}

for _, resultSet := range resultSets {
fmt.Println("IDs: ", resultSet.IDs.FieldData().GetScalars())
fmt.Println("Scores: ", resultSet.Scores)
fmt.Println("age: ", resultSet.GetColumn("age").FieldData().GetScalars())
}
curl --request POST \
--url "${CLUSTER_ENDPOINT}/v2/vectordb/entities/search" \
--header "Authorization: Bearer ${TOKEN}" \
--header "Content-Type: application/json" \
-d '{
"collectionName": "my_collection",
"data": [
[0.1, -0.2, 0.3, 0.4, 0.5]
],
"annsField": "vector",
"limit": 2,
"outputFields": ["id", "age"]
}'

#{"code":0,"cost":0,"data":[{"age":30,"distance":0.16000001,"id":1},{"age":null,"distance":0.28999996,"id":2}]}

When you use the query method for scalar filtering, the filtering results for null values are all false, indicating that they will not be selected.

# Reviewing previously inserted data:
# {"id": 1, "vector": [0.1, 0.2, ..., 0.128], "age": 30}
# {"id": 2, "vector": [0.2, 0.3, ..., 0.129], "age": None}
# {"id": 3, "vector": [0.3, 0.4, ..., 0.130], "age": None} # Omitted age column is treated as None

results = client.query(
collection_name="my_collection",
filter="age >= 0",
output_fields=["id", "age"]
)

# Example output:
# [
# {"id": 1, "age": 30}
# ]
# Note: Entities with `age` as `null` (id 2 and 3) will not appear in the result.
import io.milvus.v2.service.vector.request.QueryReq;
import io.milvus.v2.service.vector.response.QueryResp;

QueryResp resp = client.query(QueryReq.builder()
.collectionName("my_collection")
.filter("age >= 0")
.outputFields(Arrays.asList("id", "age"))
.build());

System.out.println(resp.getQueryResults());

// Output
//
// [QueryResp.QueryResult(entity={id=1, age=30})]
const results = await client.query(
collection_name: "my_collection",
filter: "age >= 0",
output_fields: ["id", "age"]
);
resultSet, err := client.Query(ctx, milvusclient.NewQueryOption("my_collection").
WithFilter("age >= 0").
WithOutputFields("id", "age"))
if err != nil {
fmt.Println(err.Error())
// handle error
}
fmt.Println("id: ", resultSet.GetColumn("id").FieldData().GetScalars())
fmt.Println("age: ", resultSet.GetColumn("age").FieldData().GetScalars())
curl --request POST \
--url "${CLUSTER_ENDPOINT}/v2/vectordb/entities/query" \
--header "Authorization: Bearer ${TOKEN}" \
--header "Content-Type: application/json" \
-d '{
"collectionName": "my_collection",
"filter": "age >= 0",
"outputFields": ["id", "age"]
}'

# {"code":0,"cost":0,"data":[{"age":30,"id":1}]}

To return entities with null values, query without any scalar filtering condition as follows:

The query method, when used without any filtering conditions, retrieves all entities in the collection, including those with null values. To restrict the number of returned entities, the limit parameter must be specified.

null_results = client.query(
collection_name="my_collection",
filter="", # Query without any filtering condition
output_fields=["id", "age"],
limit=10
)

# Example output:
# [{"id": 2, "age": None}, {"id": 3, "age": None}]
QueryResp resp = client.query(QueryReq.builder()
.collectionName("my_collection")
.filter("")
.outputFields(Arrays.asList("id", "age"))
.limit(10)
.build());

System.out.println(resp.getQueryResults());
const results = await client.query(
collection_name: "my_collection",
filter: "",
output_fields: ["id", "age"],
limit: 10
);
resultSet, err = client.Query(ctx, milvusclient.NewQueryOption("my_collection").
WithFilter("").
WithLimit(10).
WithOutputFields("id", "age"))
if err != nil {
fmt.Println(err.Error())
// handle error
}
fmt.Println("id: ", resultSet.GetColumn("id"))
fmt.Println("age: ", resultSet.GetColumn("age"))
curl --request POST \
--url "${CLUSTER_ENDPOINT}/v2/vectordb/entities/query" \
--header "Authorization: Bearer ${TOKEN}" \
--header "Content-Type: application/json" \
-d '{
"collectionName": "my_collection",
"expr": "",
"outputFields": ["id", "age"],
"limit": 10
}'

# {"code":0,"cost":0,"data":[{"age":30,"id":1},{"age":null,"id":2},{"age":null,"id":3}]}

Default values

Default values are preset values assigned to scalar fields. If you do not provide a value for a field with a default during insertion, the system automatically uses the default value.

Set default values

When creating a collection, use the default_value parameter to define the default value for a field. The following example shows how to set the default value of age to 18 and status to "active":

schema = client.create_schema(
auto_id=False,
enable_dynamic_schema=True,
)

schema.add_field(field_name="id", datatype=DataType.INT64, is_primary=True)
schema.add_field(field_name="vector", datatype=DataType.FLOAT_VECTOR, dim=5)
schema.add_field(field_name="age", datatype=DataType.INT64, default_value=18)
schema.add_field(field_name="status", datatype=DataType.VARCHAR, default_value="active", max_length=10)

index_params = client.prepare_index_params()
index_params.add_index(field_name="vector", index_type="AUTOINDEX", metric_type="L2")

client.create_collection(collection_name="my_collection", schema=schema, index_params=index_params)
import io.milvus.v2.common.DataType;
import io.milvus.v2.common.IndexParam;
import io.milvus.v2.service.collection.request.AddFieldReq;
import io.milvus.v2.service.collection.request.CreateCollectionReq;

import java.util.*;

CreateCollectionReq.CollectionSchema schema = client.createSchema();
schema.setEnableDynamicField(true);

schema.addField(AddFieldReq.builder()
.fieldName("id")
.dataType(DataType.Int64)
.isPrimaryKey(true)
.build());

schema.addField(AddFieldReq.builder()
.fieldName("vector")
.dataType(DataType.FloatVector)
.dimension(5)
.build());

schema.addField(AddFieldReq.builder()
.fieldName("age")
.dataType(DataType.Int64)
.defaultValue(18L)
.build());

schema.addField(AddFieldReq.builder()
.fieldName("status")
.dataType(DataType.VarChar)
.maxLength(10)
.defaultValue("active")
.build());

List<IndexParam> indexes = new ArrayList<>();
Map<String,Object> extraParams = new HashMap<>();

indexes.add(IndexParam.builder()
.fieldName("vector")
.indexType(IndexParam.IndexType.AUTOINDEX)
.metricType(IndexParam.MetricType.L2)
.build());

CreateCollectionReq requestCreate = CreateCollectionReq.builder()
.collectionName("my_collection")
.collectionSchema(schema)
.indexParams(indexes)
.build();
client.createCollection(requestCreate);
import { MilvusClient, DataType } from "@zilliz/milvus2-sdk-node";

const client = new MilvusClient({
address: "http://localhost:19530",
token: "root:Milvus",
});

await client.createCollection({
collection_name: "my_collection",
schema: [
{
name: "id",
is_primary_key: true,
data_type: DataType.int64,
},
{ name: "vector", data_type: DataType.FloatVector, dim: 5 },
{ name: "age", data_type: DataType.Int64, default_value: 18 },
{ name: 'status', data_type: DataType.VarChar, max_length: 30, default_value: 'active'},
],

index_params: [
{
index_name: "vector_inde",
field_name: "vector",
metric_type: MetricType.L2,
index_type: IndexType.AUTOINDEX,
},
],
});

import (
"context"
"fmt"

"github.com/milvus-io/milvus/client/v2/column"
"github.com/milvus-io/milvus/client/v2/entity"
"github.com/milvus-io/milvus/client/v2/index"
"github.com/milvus-io/milvus/client/v2/milvusclient"
)

ctx, cancel := context.WithCancel(context.Background())
defer cancel()

milvusAddr := "localhost:19530"

client, err := milvusclient.New(ctx, &milvusclient.ClientConfig{
Address: milvusAddr,
})
if err != nil {
fmt.Println(err.Error())
// handle error
}

schema := entity.NewSchema()
schema.WithField(entity.NewField().
WithName("id").
WithDataType(entity.FieldTypeInt64).
WithIsPrimaryKey(true),
).WithField(entity.NewField().
WithName("vector").
WithDataType(entity.FieldTypeFloatVector).
WithDim(5),
).WithField(entity.NewField().
WithName("age").
WithDataType(entity.FieldTypeInt64).
WithDefaultValueLong(18),
).WithField(entity.NewField().
WithName("status").
WithDataType(entity.FieldTypeVarChar).
WithMaxLength(10).
WithDefaultValueString("active"),
)

indexOption := milvusclient.NewCreateIndexOption("my_collection", "vector",
index.NewAutoIndex(index.MetricType(entity.L2)))

err = client.CreateCollection(ctx,
milvusclient.NewCreateCollectionOption("my_collection", schema).
WithIndexOptions(indexOption))
if err != nil {
fmt.Println(err.Error())
// handle error
}
export pkField='{
"fieldName": "id",
"dataType": "Int64",
"isPrimary": true
}'

export vectorField='{
"fieldName": "vector",
"dataType": "FloatVector",
"elementTypeParams": {
"dim": 5
}
}'

export defaultValueField1='{
"fieldName": "age",
"dataType": "Int64",
"defaultValue": 18
}'

export defaultValueField2='{
"fieldName": "status",
"dataType": "VarChar",
"defaultValue": "active",
"elementTypeParams": {
"max_length": 10
}
}'

export schema="{
\"autoID\": false,
\"fields\": [
$pkField,
$vectorField,
$defaultValueField1,
$defaultValueField2
]
}"

export indexParams='[
{
"fieldName": "vector",
"metricType": "L2",
"indexType": "AUTOINDEX"
}
]'

curl --request POST \
--url "${CLUSTER_ENDPOINT}/v2/vectordb/collections/create" \
--header "Authorization: Bearer ${TOKEN}" \
--header "Content-Type: application/json" \
-d "{
\"collectionName\": \"my_collection\",
\"schema\": $schema,
\"indexParams\": $indexParams
}"

Insert entities

When inserting data, if you omit fields with a default value or set their value to null, the system uses the default value:

data = [
{"id": 1, "vector": [0.1, 0.2, ..., 0.128], "age": 30, "status": "premium"},
{"id": 2, "vector": [0.2, 0.3, ..., 0.129]}, # `age` and `status` use default values
{"id": 3, "vector": [0.3, 0.4, ..., 0.130], "age": 25, "status": None}, # `status` uses default value
{"id": 4, "vector": [0.4, 0.5, ..., 0.131], "age": None, "status": "inactive"} # `age` uses default value
]

client.insert(collection_name="my_collection", data=data)
import com.google.gson.Gson;
import com.google.gson.JsonObject;

import io.milvus.v2.service.vector.request.InsertReq;
import io.milvus.v2.service.vector.response.InsertResp;

List<JsonObject> rows = new ArrayList<>();
Gson gson = new Gson();
rows.add(gson.fromJson("{\"id\": 1, \"vector\": [0.1, 0.2, 0.3, 0.4, 0.5], \"age\": 30, \"status\": \"premium\"}", JsonObject.class));
rows.add(gson.fromJson("{\"id\": 2, \"vector\": [0.2, 0.3, 0.4, 0.5, 0.6]}", JsonObject.class));
rows.add(gson.fromJson("{\"id\": 3, \"vector\": [0.3, 0.4, 0.5, 0.6, 0.7], \"age\": 25, \"status\": null}", JsonObject.class));
rows.add(gson.fromJson("{\"id\": 4, \"vector\": [0.4, 0.5, 0.6, 0.7, 0.8], \"age\": null, \"status\": \"inactive\"}", JsonObject.class));

InsertResp insertR = client.insert(InsertReq.builder()
.collectionName("my_collection")
.data(rows)
.build());
const data = [
{"id": 1, "vector": [0.1, 0.2, 0.3, 0.4, 0.5], "age": 30, "status": "premium"},
{"id": 2, "vector": [0.2, 0.3, 0.4, 0.5, 0.6]},
{"id": 3, "vector": [0.3, 0.4, 0.5, 0.6, 0.7], "age": 25, "status": null},
{"id": 4, "vector": [0.4, 0.5, 0.6, 0.7, 0.8], "age": null, "status": "inactive"}
];

client.insert({
collection_name: "my_collection",
data: data,
});
column1, _ := column.NewNullableColumnInt64("age",
[]int64{30, 25},
[]bool{true, false, true, false})
column2, _ := column.NewNullableColumnVarChar("status",
[]string{"premium", "inactive"},
[]bool{true, false, false, true})

_, err = client.Insert(ctx, milvusclient.NewColumnBasedInsertOption("my_collection").
WithInt64Column("id", []int64{1, 2, 3, 4}).
WithFloatVectorColumn("vector", 5, [][]float32{
{0.1, 0.2, 0.3, 0.4, 0.5},
{0.2, 0.3, 0.4, 0.5, 0.6},
{0.3, 0.4, 0.5, 0.6, 0.7},
{0.4, 0.5, 0.6, 0.7, 0.8},
}).
WithColumns(column1, column2),
)
if err != nil {
fmt.Println(err.Error())
// handle err
}
curl --request POST \
--url "${CLUSTER_ENDPOINT}/v2/vectordb/entities/insert" \
--header "Authorization: Bearer ${TOKEN}" \
--header "Content-Type: application/json" \
-d '{
"data": [
{"id": 1, "vector": [0.1, 0.2, 0.3, 0.4, 0.5], "age": 30, "status": "premium"},
{"id": 2, "vector": [0.2, 0.3, 0.4, 0.5, 0.6]},
{"id": 3, "vector": [0.3, 0.4, 0.5, 0.6, 0.7], "age": 25, "status": null},
{"id": 4, "vector": [0.4, 0.5, 0.6, 0.7, 0.8], "age": null, "status": "inactive"}
],
"collectionName": "my_collection"
}'

For more information on how nullable and default value settings take effect, refer to Applicable rules.

Search and query with default values

Entities that contain default values are treated the same as any other entities during vector searches and scalar filtering. You can include default values as part of your search and query operations.

For example, in a search operation, entities with age set to the default value of 18 will be included in the results:

res = client.search(
collection_name="my_collection",
data=[[0.1, 0.2, 0.4, 0.3, 0.5]],
search_params={"params": {"nprobe": 16}},
filter="age == 18", # 18 is the default value of the `age` field
limit=10,
output_fields=["id", "age", "status"]
)

print(res)

# Output
# data: ["[{'id': 2, 'distance': 0.050000004, 'entity': {'id': 2, 'age': 18, 'status': 'active'}}, {'id': 4, 'distance': 0.45000002, 'entity': {'id': 4, 'age': 18, 'status': 'inactive'}}]"]

import io.milvus.v2.service.vector.request.SearchReq;
import io.milvus.v2.service.vector.request.data.FloatVec;
import io.milvus.v2.service.vector.response.SearchResp;

Map<String,Object> params = new HashMap<>();
params.put("nprobe", 16);
SearchResp resp = client.search(SearchReq.builder()
.collectionName("my_collection")
.annsField("vector")
.data(Collections.singletonList(new FloatVec(new float[]{0.1f, 0.2f, 0.3f, 0.4f, 0.5f})))
.searchParams(params)
.filter("age == 18")
.topK(10)
.outputFields(Arrays.asList("id", "age", "status"))
.build());

System.out.println(resp.getSearchResults());

// Output
//
// [[SearchResp.SearchResult(entity={id=2, age=18, status=active}, score=0.050000004, id=2), SearchResp.SearchResult(entity={id=4, age=18, status=inactive}, score=0.45000002, id=4)]]
client.search({
collection_name: 'my_collection',
data: [0.3, -0.6, 0.1, 0.3, 0.5],
limit: 2,
output_fields: ['age', 'id', 'status'],
filter: 'age == 18',
params: {
nprobe: 16
}
});
queryVector := []float32{0.1, 0.2, 0.4, 0.3, 0.5}

annParam := index.NewCustomAnnParam()
annParam.WithExtraParam("nprobe", 16)
resultSets, err := client.Search(ctx, milvusclient.NewSearchOption(
"my_collection", // collectionName
10, // limit
[]entity.Vector{entity.FloatVector(queryVector)},
).WithANNSField("vector").
WithFilter("age == 18").
WithAnnParam(annParam).
WithOutputFields("id", "age", "status"))
if err != nil {
fmt.Println(err.Error())
// handle error
}

for _, resultSet := range resultSets {
fmt.Println("IDs: ", resultSet.IDs.FieldData().GetScalars())
fmt.Println("Scores: ", resultSet.Scores)
fmt.Println("age: ", resultSet.GetColumn("age").FieldData().GetScalars())
fmt.Println("status: ", resultSet.GetColumn("status").FieldData().GetScalars())
}
curl --request POST \
--url "${CLUSTER_ENDPOINT}/v2/vectordb/entities/search" \
--header "Authorization: Bearer ${TOKEN}" \
--header "Content-Type: application/json" \
-d '{
"collectionName": "my_collection",
"data": [
[0.1, 0.2, 0.3, 0.4, 0.5]
],
"annsField": "vector",
"limit": 10,
"filter": "age == 18",
"outputFields": ["id", "age", "status"]
}'

# {"code":0,"cost":0,"data":[{"age":18,"distance":0.050000004,"id":2,"status":"active"},{"age":18,"distance":0.45000002,"id":4,"status":"inactive"}]}

In a query operation, you can match or filter by default values directly:

# Query all entities where `age` equals the default value (18)
default_age_results = client.query(
collection_name="my_collection",
filter="age == 18",
output_fields=["id", "age", "status"]
)

# Query all entities where `status` equals the default value ("active")
default_status_results = client.query(
collection_name="my_collection",
filter='status == "active"',
output_fields=["id", "age", "status"]
)
import io.milvus.v2.service.vector.request.QueryReq;
import io.milvus.v2.service.vector.response.QueryResp;

QueryResp ageResp = client.query(QueryReq.builder()
.collectionName("my_collection")
.filter("age == 18")
.outputFields(Arrays.asList("id", "age", "status"))
.build());

System.out.println(ageResp.getQueryResults());

// Output
//
// [QueryResp.QueryResult(entity={id=2, age=18, status=active}), QueryResp.QueryResult(entity={id=4, age=18, status=inactive})]

QueryResp statusResp = client.query(QueryReq.builder()
.collectionName("my_collection")
.filter("status == \"active\"")
.outputFields(Arrays.asList("id", "age", "status"))
.build());

System.out.println(statusResp.getQueryResults());

// Output
//
// [QueryResp.QueryResult(entity={id=2, age=18, status=active}), QueryResp.QueryResult(entity={id=3, age=25, status=active})]
// Query all entities where `age` equals the default value (18)
const default_age_results = await client.query(
collection_name: "my_collection",
filter: "age == 18",
output_fields: ["id", "age", "status"]
);
// Query all entities where `status` equals the default value ("active")
const default_status_results = await client.query(
collection_name: "my_collection",
filter: 'status == "active"',
output_fields: ["id", "age", "status"]
)
resultSet, err := client.Query(ctx, milvusclient.NewQueryOption("my_collection").
WithFilter("age == 18").
WithOutputFields("id", "age", "status"))
if err != nil {
fmt.Println(err.Error())
// handle error
}
fmt.Println("id: ", resultSet.GetColumn("id").FieldData().GetScalars())
fmt.Println("age: ", resultSet.GetColumn("age").FieldData().GetScalars())
fmt.Println("status: ", resultSet.GetColumn("status").FieldData().GetScalars())

resultSet, err = client.Query(ctx, milvusclient.NewQueryOption("my_collection").
WithFilter("status == \"active\"").
WithOutputFields("id", "age", "status"))
if err != nil {
fmt.Println(err.Error())
// handle error
}
fmt.Println("id: ", resultSet.GetColumn("id").FieldData().GetScalars())
fmt.Println("age: ", resultSet.GetColumn("age").FieldData().GetScalars())
fmt.Println("status: ", resultSet.GetColumn("status").FieldData().GetScalars())
curl --request POST \
--url "${CLUSTER_ENDPOINT}/v2/vectordb/entities/query" \
--header "Authorization: Bearer ${TOKEN}" \
--header "Content-Type: application/json" \
-d '{
"collectionName": "my_collection",
"filter": "age == 18",
"outputFields": ["id", "age", "status"]
}'

# {"code":0,"cost":0,"data":[{"age":18,"id":2,"status":"active"},{"age":18,"id":4,"status":"inactive"}]}

curl --request POST \
--url "${CLUSTER_ENDPOINT}/v2/vectordb/entities/query" \
--header "Authorization: Bearer ${TOKEN}" \
--header "Content-Type: application/json" \
-d '{
"collectionName": "my_collection",
"filter": "status == \"active\"",
"outputFields": ["id", "age", "status"]
}'

# {"code":0,"cost":0,"data":[{"age":18,"id":2,"status":"active"},{"age":25,"id":3,"status":"active"}]}

Applicable rules

The following table summarizes the behavior of nullable columns and default values under different configuration combinations. These rules determine how Milvus handles data when attempting to insert null values or if field values are not provided.

Nullable

Default Value

Default Value Type

User Input

Result

Example

Non-null

None/null

Uses the default value

Field: age Default value: 18

User input: null

Result: stored as 18

-

None/null

Stored as null

Field: middle_name Default value: -

User input: null

Result: stored as null

Non-null

None/null

Uses the default value

Field: status Default value: "active"

User input: null

Result: stored as "active"

-

None/null

Throws an error

Field: email Default value: -

User input: null

Result: Operation rejected, system throws an error

Null

None/null

Throws an error

Field: username Default value: null

User input: null

Result: Operation rejected, system throws an error