Manage databases

Prerequisites

• The PyMilvus library is installed on your local client and is updated to the latest version.

  To install or update the PyMilvus library, run the following command.

  pip install --upgrade pymilvus

• A Milvus instance has been created. For more information, see Create a Milvus instance.

• A connection to the Milvus instance has been established. The following code shows an example.

  from pymilvus import connections, db
  
  conn = connections.connect(
     host="c-xxx.milvus.aliyuncs.com",  # The public endpoint of the Milvus instance.
     port=19530,                        # The port used by the proxy. The default is 19530.
     user="<yourUsername>",             # The username for the Milvus instance.
     password="<yourPassword>"         # The password for the username.
  )

Limits

By default, a Milvus instance supports a maximum of 64 databases.

Create a database

Connect to a Milvus instance and specify a name for the database that you want to create.

database = db.create_database("<yourDbname>")

<yourDbname> is the name of the database to create. This topic uses milvus_demo as an example. You can change the name as needed.

Use a database

By default, a Milvus instance includes a database named default. Unless specified otherwise, all collections are created in the default database. To switch to a different database for subsequent operations, run the following statement.

db.using_database("milvus_demo")

You can also specify an existing database when you connect to Milvus.

conn = connections.connect(host="c-xxx.milvus.aliyuncs.com", port=19530, user="<yourUsername>", password="<yourPassword>", db_name="milvus_demo")

List databases

Run the following command to list all databases in the Milvus instance.

db.list_database()

Delete a database

Before you delete a database, you must purge all collections within it. A database that contains collections cannot be deleted.

db.drop_database("milvus_demo")

References

For more information, see Manage users and roles.