lastval
lastval — aggregate function to return the last value from a specified column.
DESCRIPTION
This function returns the last non-null value, if any, in the range of values returned by its query predicate.
Expression expr
must contain the name of a column in a LiveView table. The returned last value is of the same type as the specified column.
If the query returns no rows, the aggregate returns null
.
EXAMPLE
This example shows a simple use of the lastval() function.
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In LiveView Desktop connected to a server running the Hello LiveView sample, select the ItemsSales table from the Tables pane of the LiveView Tables view.
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In the Select field, enter:
lastval(Item) as Last
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Make sure the Query field is empty.
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Click
.
The query results open in a grid view. The value continuously updates as new values arrive.
SEE ALSO
This LiveView aggregate function is based on the lastval aggregate function in the StreamBase expression language.