Python API

Important:

The release notes for version 1.30.19.1 and later can be found in the full documentation of DolphinDB Python API. Please refer to Release Notes page - Python API for details.

For new features and changes introduced in earlier versions of the DolphinDB Python API up to 1.30.17.3, please see the list below.

  • Fixed the issue where the creation of objects in class DBConnectionPool fails when the parameter loadBalance is set to True. (1.30.17.3)

  • Fixed the issue where uploading a DataFrame fails if the first row of a string column is None. (1.30.17.4)

  • Support NumPy 1.22.3 and Pandas 1.4.2 (excluding Pandas 1.3.0). (1.30.17.2)

  • You can import a DataFrame with arrays to DolphinDB as a table with array vectors. (1.30.17.2)

  • Fixed issues of uploading and downloading any vectors. (1.30.17.2)

  • Changed the data type of errorCode of Class ErrorCodeInfo from int to string. (1.30.17.2)

  • Added new methods hasError and succeed to check whether the data is written properly. (1.30.17.2)

  • Added new class MultithreadedTableWriter for multi-threaded writes to partitioned DFS tables, in-memory tables and dimension tables, with support for SSL communication, compressed communication, high-availability data writes and more. (1.30.17.1)

  • New parameter compress for session objects for dowloading compressed data. (1.30.17.1)

  • Reduced the time taken by the Python Global Interpreter Lock (GIL) in a session. (1.30.17.1)

  • Added new method toList for table objects for converting array vectors to 2D arrays. (1.30.17.1)

  • PartitionedTableAppender now supports automatic temporal type conversion for table writes. (1.30.17.1)

  • Added new parameters engine, atomic, enableChunkGranularityConfig for session.database. Note that these parameters are only supported in the TSDB engine (provided in DolphinDB server 2.00.0 and later). (1.30.17.1)

  • Added new parameters compressMethods, sortColumns, keepDuplicates to database.createPartitionedTable. Note that these parameters are only supported in the TSDB engine (provided in DolphinDB server 2.00.0 and later). (1.30.17.1)

  • Fixed the data loss issue with session.subscribe. (1.30.17.1)

  • Adjusted the version numbering scheme of Python API to keep it consistent with that of the DolphinDB server. (1.30.16.1)

  • Connection to 200 and later versions of DolphinDB server is now supported. (1.30.16.1)

  • Upload and download of array vectors are now supported. (1.30.16.1)

  • Added new parameter keepAliveTime for the Session class method connect() to specify the duration between two keepalive transmissions. The default value is 30 (seconds). Specify a greater value for this parameter when querying large amount of data to avoid disconnections. (1.30.0.15)

  • orca: Fixed the issue with the function orca.panel. (1.30.0.10)

  • orca: New function for calculating the rolling rank. (1.30.0.9)

  • orca: Support for calculating weighted rolling mean. (1.30.0.9)

  • orca: New function orca.read_in_memory_table for querying DolphinDB in-memory tables. (1.30.0.9)

  • orca: New function orca.panel. (1.30.0.9)

  • orca: Fixed the issue that the specified where condition took no effect in window join. (1.30.0.9)

  • orca: Removed the lazy parameter from groupby as it only supports lazy evaluation now. (1.30.0.9)

  • New method runTaskAsyn for DBConnectionPool to provide a convenient way to execute asynchronous tasks concurrently. (1.30.0.8)

  • Fixed the issue that the where condition specified in update took no effect. (1.30.0.8)

  • Fixed a client crash issue when appending data asynchronously to database via Python API. (1.30.0.8)

  • Fixed the error that occurred when the name of the named object uploaded via Python API was the same as that of the named object in a previous upload. (1.30.0.8)

  • Removed the restriction that the pandas version must be lower than 1.0 for Python API installation. (1.30.0.7)

  • Added partitionedTableAppender for concurrent writes to a partitioned DFS table. (1.30.0.6)

  • Added new parameter fetchSize to run to specify the number of rows retrieved each time. (1.30.0.6)

  • Support for batch processing in streaming data subscription. (1.30.0.6)

  • Added new parameter clearMemory to automatically clear the variables generated within a session once the execution of run is completed. (1.30.0.6)

  • Version compatibility check is performed when connecting to DolphinDB server. (1.30.0.6)

  • When writing a DataFrame to DolphinDB via tableAppender, the date and time types in the DataFrame are automatically converted to the date and time types specified by the target table. (1.30.0.6)

  • Optimized data transmission performance. To connect to the latest DolphinDB server, upgrade Python API to 1.30.0.5 via pip3 install dolphindb==1.30.0.5. (1.30.0.5)