Manage Databases

Similar to traditional database engines, you can also create databases in Milvus and allocate privileges to certain users to manage them. Then such users have the right to manage the collections in the databases. A Milvus cluster supports a maximum of 64 databases.

Create database

To create a database, you need to first connect to a Milvus cluster and prepare a name for it:

Python Java C#

from pymilvus import connections, db

conn = connections.connect(host="127.0.0.1", port=19530)

database = db.create_database("book")

import io.milvus.client.*;
import io.milvus.param.*;

ConnectParam connectParam = ConnectParam.newBuilder()
    .withHost("127.0.0.1")
    .withPort(19530)
    .build();

MilvusClient client = new MilvusServiceClient(connectParam);

CreateDatabaseParam createDatabaseParam = CreateDatabaseParam.newBuilder()
    .withDatabaseName("book")
    .build();

R<RpcStatus> createDatabaseResponse = client.createDatabase(createDatabaseParam);

if (createDatabaseResponse.getStatus() != R.Status.Success.getCode()) {
    System.out.println(createDatabaseResponse.getMessage());
}

using Milvus.Client

MilvusClient milvusClient = new MilvusClient(host: "127.0.0.1", port: 19530);

await milvusClient.CreateDatabaseAsync("book");

Use a database

A Milvus cluster ships with a default database, named 'default'. Collections are created in the default database unless otherwise specified.

To change the default database, do as follows:

Python Java C#

db.using_database("book")

// No equivalent method available.
// Disconnect first and connect again with a specific database.
// See below

// No equivalent method available.
// Disconnect first and connect again with a specific database.
// See below

You can also set a database to use upon connecting to your Milvus cluster as follows:

Python Java C#

conn = connections.connect(
    host="127.0.0.1",
    port="19530",
    db_name="default"
)

ConnectParam connectParam = ConnectParam.newBuilder()
    .withHost("127.0.0.1")
    .withPort(19530)
    .withDatabaseName("default")
    .build();

MilvusClient client = new MilvusServiceClient(connectParam);

MilvusClient milvusClient = new MilvusClient(host: "127.0.0.1", database: "book");

List databases

To find all existing databases in your Milvus cluster, do as follows:

Python Java C#

db.list_database()

# Output
# ['default', 'book']

R<ListDatabasesResponse> response = client.listDatabases();

int dbCounts = response.getData().getDbNamesCount();

for (int i = 0; i < dbCounts; i++) {
    System.out.println(response.getData().getDbNames(i));
}

// Output:
//
// default
// book

var databases = await milvusClient.ListDatabasesAsync();

foreach (var database in databases) {
    Console.WriteLine(database);
}

// Output
//
// default
// book

Drop database

To drop a database, you have to drop all its collections first. Otherwise, the drop fails.

Python Java C#

db.drop_database("book")

db.list_database()

# Output
# ['default']

DropDatabaseParam dropDatabaseParam = DropDatabaseParam.newBuilder()
    .withDatabaseName("book")
    .build();

R<RpcStatus> dropDatabaseResponse = client.dropDatabase(dropDatabaseParam);

R<ListDatabasesResponse> response = client.listDatabases();

int dbCounts = response.getData().getDbNamesCount();

for (int i = 0; i < dbCounts; i++) {
    System.out.println(response.getData().getDbNames(i));
}

// Output:
//
// default

await milvusClient.DropDatabaseAsync("book");

var databases = await milvusClient.ListDatabasesAsync();

foreach (var database in databases) {
    Console.WriteLine(database);
}

// Output
//
// default

Use the RBAC with database

RBAC also covers database operations and ensures forward compatibility. The word database in the Permission APIs (Grant / Revoke / List Grant) has the following meanings:

If neither a Milvus connection nor a Permission API call specifies a db_name, database refers to the default database.
If a Milvus connection specifies a db_name, but a Permission API call afterward does not, database refers to the database whose name was specified in the Milvus connection.
If a Permission API call is made upon a Milvus connection, with or without db_name specified, database refers to the database whose name was specified in the Permission API call.

The following code snippet is shared among the listed blocks below.

Python Java C#

from pymilvus import connections, Role

_HOST = '127.0.0.1'
_PORT = '19530'
_ROOT = "root"
_ROOT_PASSWORD = "Milvus"
_ROLE_NAME = "test_role"
_PRIVILEGE_INSERT = "Insert"


def connect_to_milvus(db_name="default"):
    print(f"connect to milvus\n")
    connections.connect(host=_HOST, port=_PORT, user=_ROOT, password=_ROOT_PASSWORD, db_name=db_name)

static String _HOST = "localhost";
static int _PORT = 19530;
static String _ROOT = "root";
static String _ROOT_PASSWORD = "Milvus";
static String _ROLE_NAME = "test_role";
static String _PRIVILEGE_INSERT = "Insert";

// With specific database
public static MilvusClient ConnectToMilvus(String DbName) {
    System.out.println("Start connecting to Milvus");

    ConnectParam connectParam = ConnectParam.newBuilder()
        .withHost(App._HOST)
        .withPort(App._PORT)
        .withAuthorization(App._ROOT, App._ROOT_PASSWORD)
        .withDatabaseName(DbName)
        .build();

    MilvusClient client = new MilvusServiceClient(connectParam);

    return client;
}

// With the default database
public static MilvusClient ConnectToMilvus() {
    System.out.println("Start connecting to Milvus");

    ConnectParam connectParam = ConnectParam.newBuilder()
        .withHost(App._HOST)
        .withPort(App._PORT)
        .withAuthorization(App._ROOT, App._ROOT_PASSWORD)
        .build();

    MilvusClient client = new MilvusServiceClient(connectParam);

    return client;
}

string _HOST = "127.0.0.1";
string _ROOT = "root";
string _ROOT_PASSWORD = "Milvus";
string _ROLE_NAME = "test_role";
string _PRIVILEGE_INSERT = "Insert";

MilvusClient connect_to_milvus(string db_name="default") {
    MilvusClient milvusClient = new MilvusClient(host: _HOST, username: _ROOT, password: _ROOT_PASSWORD, database: db_name);

    return milvusClient;
}

If neither a Milvus connection nor a Permission API call specifies a db_name, database refers to the default database.

Python Java C#

connect_to_milvus()
role = Role(_ROLE_NAME)
role.create()

connect_to_milvus()
role.grant("Collection", "*", _PRIVILEGE_INSERT)
print(role.list_grants())
print(role.list_grant("Collection", "*"))
role.revoke("Global", "*", _PRIVILEGE_INSERT)

MilvusClient client = ConnectToMilvus()

CreateRoleParam createRoleParam = CreateRoleParam.newBuilder()
    .withRoleName(App._ROLE_NAME)
    .build();

R<RpcStatus> response = client.createRole(createRoleParam);

GrantRolePrivilegeParam grantRolePriviligeParam = GrantRolePrivilegeParam.newBuilder()
    .withRoleName(App._ROLE_NAME)
    .withPrivilege(App._PRIVILEGE_INSERT)
    .withObject("Collection")
    .withObjectName("*")
    .build(); 

R<RpcStatus> response = client.grantRolePrivilege(grantRolePriviligeParam);

SelectGrantForRoleParam selectGrantForRoleParam = SelectGrantForRoleParam.newBuilder()
    .withRoleName(App._ROLE_NAME)
    .build();

R<SelectGrantResponse> response = client.selectGrantForRole(selectGrantForRoleParam);

System.out.println(response.getData());

MilvusClient client = connect_to_milvus();

try {
    await client.CreateRoleAsync(_ROLE_NAME);
} catch (Exception) {
    Console.WriteLine("Already exists!");
}

await client.GrantRolePrivilegeAsync(_ROLE_NAME, @object: "Collection", objectName: "*", privilege: _PRIVILEGE_INSERT);

var grants1 = await client.ListGrantsForRoleAsync(_ROLE_NAME);

for (int i = 0; i < grants1.Count; i++) {
    var grant = grants1[i];
    Console.WriteLine(grant.Role);
    Console.WriteLine(grant.Grantor.UserName);
    Console.WriteLine(grant.DbName);
    Console.WriteLine(grant.ObjectName);
}

await client.RevokeRolePrivilegeAsync(_ROLE_NAME, @object: "Collection", objectName: "*", privilege: _PRIVILEGE_INSERT);

var grants2 = await client.SelectGrantForRoleAndObjectAsync(_ROLE_NAME, @object: "Collection", objectName: "*");

for (int i = 0; i< grants2.Count; i++) {
    var grant = grants2[i];
    Console.WriteLine(grant.Role);
    Console.WriteLine(grant.Grantor.UserName);
    Console.WriteLine(grant.DbName);
    Console.WriteLine(grant.ObjectName);    
}

If a Milvus connection specifies a db_name, but a Permission API call afterward does not, database refers to the database whose name was specified in the Milvus connection.

Python Java C#

# NOTE: please make sure the 'book' db has been created
connect_to_milvus(db_name="book")
# This role will have the insert permission of all collections under foo db,
# excluding the insert permissions of collections under other dbs
role.grant("Collection", "*", _PRIVILEGE_INSERT)
print(role.list_grants())
print(role.list_grant("Collection", "*"))
role.revoke("Global", "*", _PRIVILEGE_INSERT)

MilvusClient client = ConnectToMilvus("book")

GrantRolePrivilegeParam grantRolePriviligeParam = GrantRolePrivilegeParam.newBuilder()
    .withRoleName(App._ROLE_NAME)
    .withPrivilege(App._PRIVILEGE_INSERT)
    .withObject("Collection")
    .withObjectName("*")
    .build(); 

R<RpcStatus> response = client.grantRolePrivilege(grantRolePriviligeParam);

SelectGrantForRoleParam selectGrantForRoleParam = SelectGrantForRoleParam.newBuilder()
    .withRoleName(App._ROLE_NAME)
    .build();

R<SelectGrantResponse> response = client.selectGrantForRole(selectGrantForRoleParam);

System.out.println(response.getData());

// NOTE: please make sure the 'book' db has been created
MilvusClient client = connect_to_milvus(db_name: "book");

try {
    await client.CreateRoleAsync(_ROLE_NAME);
} catch (Exception) {
    Console.WriteLine("Already exists!");
}

// This role will have the insert permission of all collections under foo db,
// excluding the insert permissions of collections under other dbs
await client.GrantRolePrivilegeAsync(_ROLE_NAME, @object: "Collection", objectName: "*", privilege: _PRIVILEGE_INSERT);

var grants1 = await client.ListGrantsForRoleAsync(_ROLE_NAME);

for (int i = 0; i < grants1.Count; i++) {
    var grant = grants1[i];
    Console.WriteLine(grant.Role);
    Console.WriteLine(grant.Grantor.UserName);
    Console.WriteLine(grant.DbName);
    Console.WriteLine(grant.ObjectName);
}

await client.RevokeRolePrivilegeAsync(_ROLE_NAME, @object: "Collection", objectName: "*", privilege: _PRIVILEGE_INSERT);

var grants2 = await client.SelectGrantForRoleAndObjectAsync(_ROLE_NAME, @object: "Collection", objectName: "*");

for (int i = 0; i< grants2.Count; i++) {
    var grant = grants2[i];
    Console.WriteLine(grant.Role);
    Console.WriteLine(grant.Grantor.UserName);
    Console.WriteLine(grant.DbName);
    Console.WriteLine(grant.ObjectName);    
}

If a Permission API call is made upon a Milvus connection, with or without db_name specified, database refers to the database whose name was specified in the Permission API call.

Python Java C#

# NOTE: please make sure the 'book' db has been created
db_name = "book"
connect_to_milvus()
role.grant("Collection", "*", _PRIVILEGE_INSERT, db_name=db_name)
print(role.list_grants(db_name=db_name))
print(role.list_grant("Collection", "*", db_name=db_name))
role.revoke("Global", "*", _PRIVILEGE_INSERT, db_name=db_name)

MilvusClient client = ConnectToMilvus()

CreateRoleParam createRoleParam = CreateRoleParam.newBuilder()
    .withRoleName(App._ROLE_NAME)
    .build();

R<RpcStatus> response = client.createRole(createRoleParam);

GrantRolePrivilegeParam grantRolePriviligeParam = GrantRolePrivilegeParam.newBuilder()
    .withRoleName(App._ROLE_NAME)
    .withPrivilege(App._PRIVILEGE_INSERT)
    .withObject("Collection")
    .withObjectName("*")
    .withDatabaseName("book")
    .build(); 

R<RpcStatus> response = client.grantRolePrivilege(grantRolePriviligeParam);

SelectGrantForRoleParam selectGrantForRoleParam = SelectGrantForRoleParam.newBuilder()
    .withRoleName(App._ROLE_NAME)
    .build();

R<SelectGrantResponse> response = client.selectGrantForRole(selectGrantForRoleParam);

System.out.println(response.getData());

// No equivalent usage available.

What's next

Enable RBAC

Multi-tenancy