DolphinDB Release Notes

DolphinDB Server

Version : 0.97.4 Release Date : 2019-08-16

Version: 0.97.3 Release Date: 2019-07-29

Version : 0.97.2 Release Date : 2019-07-24

Version : 0.97.1 Release Date : 2019-07-15

Version : 0.97.0 Release Date : 2019-07-09

New Features

Added data retention policy that enables the system to automatically delete expired data according to the given data expiration policy.
Added function saveAsNpy to save DolphinDB objects as npy files(numpy data files).
Added function loadNpy to load npy files as DolphinDB objects.
Now supports dynamically adding new partitions based on new data for the VALUE partition type. Use parameter 'newValuePartitionPolicy' to enable this feature
Added new function firstNot.
Added 3 new machine learning algorithms: K-Means, Naive Bayes and K-nearest neighbors(KNN).
When appending data to a partitioned table, if the temporal data type in the new data does not match that in the original data, the system automatically converts the temporal type in the new data to that in the original data. (0.97.3 2019-07-29)

Improvements

For COMPO partitions, function repartitionDS allows re-partitioning according to the original partition scheme of a given partition layer.
When writing to a partition on a node and the node becomes unavailable due to reasons such as power outage, as long as the partition has at least one copy on available data nodes, the writing operation will finish successfully.
Redo log configuration parameter name changes: 'logDir' is now 'redoLogDir', 'redoLogGCInterval' is now 'redoLogPurgeInterval', 'redoLogMx' is now 'redoLogPurgeLimit'.
Can set priority and parallelism of jobs in APIs (0.97.1 2019.07.15).
The template function ‘cross’ can return a scalar or a tuple. If it returns a tuple, its number of elements is the same as the dimension of X. Each element of the tuple is also a tuple. The number of elements of this tuple is the same as the dimension of Y (0.97.4 2019.08.16).
The substitution parameter in function ‘nullFill’ can be not only a scalar, but also a vector or matrix that has the same dimensions as the object being replaced (0.97.4 2019.08.16).
The ‘dfs’ keyword in the distributed database path is no longer case sensitive (0.97.4 2019.08.16).
Comments are allowed in the middle of a multiline SQL statement (0.97.4 2019.08.16).
The parameter ‘partitionScheme’ of function ‘database’ in creating VALUE partitions is not allowed to contain negative values (0.97.4 2019.08.16).

Bug fixes

Fixed the bug that the command addFunctionView fails when a functionView depends on another functionView.
Fixed a bug with command dropTable. Dropping a dfs table for multiple times may cause version inconsistency of tablet chunks. (0.97.2 2019.07.24)
don't split and-connected expression in where clause when the expression contains sequence-related function or user defined functions (0.97.4 2019.08.16).
If function replayDS over the same sql query object is executed repeatedly, the results are incorrect for the second and all subsequent executions (0.97.4 2019.08.16).

Added keyword highlights for limit, VALUE, RANGE and LIST.
Published the visual studio code plugin to support editing and executing DolphinDB scripts in visual studio code. Plugin installation

Java API

Fixed a bug in streaming API unsubscription: ThreadedClient cannot successfully unsubscribe when parameter 'actionName' is not specified.

C# API