DBConnection

DBConnection (supported since Python API 3.0.4.0) represents a single underlying connection between the client and the DolphinDB server, used to execute scripts, call functions, and upload variables.

DBConnection is recommended for single-connection scenarios, while SimpleDBConnectionPool should be used for multithreaded environments. The legacy Session interface is retained for backward compatibility (see "Migrating from Session to DBConnection" for details).

Note: Instantiating a DBConnection object does not automatically establish a connection to the server. You must call connect() before performing any operations.

import dolphindb as ddb

conn = ddb.DBConnection(protocol="ddb")
try:
    connected = conn.connect(
        host="localhost",
        port=8848,
        userid="admin",
        password="your_password",
    )
    if not connected:
        raise RuntimeError("Failed to connect to DolphinDB")

    print(conn.exec("1 + 1"))
    # output: 2
finally:
    conn.close()

Select the appropriate connection interface based on your use case:

Note: To focus on the core operations, the following examples assume that a connection has been established through conn. In production, use a try...finally block and explicitly call conn.close() to ensure that network connections and system resources are released properly.