tuple_sketch_theta_integer function

Applies to: Databricks Runtime 18.1 and above

Returns the theta value (sampling rate) from a TupleSketch with integer summaries.

Syntax

tuple_sketch_theta_integer ( sketch )

Arguments

• sketch: A TupleSketch in binary format with integer summaries.

Returns

A DOUBLE value between 0.0 and 1.0 representing the effective sampling rate of the sketch.

Notes

• Theta = 1.0 indicates the sketch has not been sampled (exact mode).
• Theta < 1.0 indicates the sketch has been probabilistically sampled.

Examples

> SELECT tuple_sketch_theta_integer(tuple_sketch_agg_integer(key, summary)) FROM VALUES (1, 1), (2, 2), (3, 3) tab(key, summary);
1.0

Related

• tuple_sketch_theta_double function
• tuple_sketch_estimate_integer function