freq_agg()

Early access 1.5.0

Aggregate data into a space-saving aggregate object, which stores frequency information in an intermediate form. You can then use any of the accessors in this group to return estimated frequencies or the most common elements.

Samples

Create a space-saving aggregate over a field ZIP in a HomeSales table. This aggregate tracks any ZIP value that occurs in at least 5% of rows:

SELECT toolkit_experimental.freq_agg(0.05, ZIP) FROM HomeSales;

Arguments

The syntax is:

freq_agg(
  min_freq DOUBLE PRECISION,
  value AnyElement
) RETURNS SpaceSavingAggregate

Name	Type	Default	Required	Description
min_freq	DOUBLE PRECISION	-	✔	Frequency cutoff for keeping track of a value. Values that occur less frequently than the cutoff are not stored.
value	AnyElement	-	✔	The column to store frequencies for

Returns

Column	Type	Description
agg	SpaceSavingAggregate	An object storing the most common elements of the given table and their estimated frequency. You can pass this object to any of the accessor functions to get a final result.