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Extending HCL OneDB™Beyond standard relational database objects, HCL OneDB™ can be extended to handle specialized data types, access methods, routines, and other objects. HCL OneDB™ includes many built-in extensions that are fully integrated in the database server. HCL OneDB™ also provides DataBlade® modules, which are packages of extended database objects for a particular purpose and that are installed separately from the database server. Alternatively, you can create your own user-defined objects for HCL OneDB™.
HCL OneDB™ extensions and DataBlade® modulesThese topics describe how to use built-in database extensions and separately installed DataBlade® modules.
TimeSeries Data User's GuideThe HCL OneDB™ TimeSeries Data User's Guide contains information to assist you in using the TimeSeries extension with HCL OneDB™.
Time series SQL routines
GetLastNonNull functionThe GetLastNonNull function returns the last non-null element on or before the date you specify.

GetLastNonNull function

The GetLastNonNull function returns the last non-null element on or before the date you specify.

Syntax

GetLastNonNull(ts          TimeSeries, 
              tstamp      datetime year to fraction(5),
              column_name lvarchar default null,
              flags       integer default 0
) 
returns row;

ts: The source time series.
tstamp: The time stamp for the element you specify.
column_name (optional): If you specify a column using the column_name argument, the GetLastNonNull function returns the last non-null element on or before the specified date that has a non-null value in the specified column.
If you do not specify the column_name argument, the GetLastNonNull function returns the last non-null element on or before the date. It is possible that all the columns except the time stamp could be NULL.
flags: Valid values for the flags argument are described in The flags argument values. The default is 0.

Description

There are no null elements in an irregular time series. Therefore, when you use the GetLastNonNull function on an irregular time series, always specify a column name. If you use the GetLastNonNull function on an irregular time series without specifying a column name, its effect is equivalent to that of the GetLastValid function.

Returns

A non-null element of the time series.