QUANTILE_DISC() GROUP BY ...

All functions > GROUP BY > QUANTILE_DISC() GROUP BY ...

Returns an element from the group at the given discrete quantile; result type matches the aggregated expression.

Syntax

QUANTILE_DISC(expr, quantile)
 [ FILTER (WHERE condition) ]
  [ GROUP BY feature [, feature ...] ]

QUANTILE_DISC(expr, quantile)
 [ FILTER (WHERE condition) ]
  [ GROUP BY feature [, feature ...] ]

Notes

• NULL values are ignored where the underlying aggregate skips NULLs
• Can be used with FILTER (WHERE condition) and GROUP BY like other aggregates
• quantile uses DOUBLE (for example 0.5e0); discrete quantiles pick an actual value from the multiset

Examples

SELECT
    -- Discrete 0.5 quantile over one group
    f1 := ZIP(ARRAY(1, 1, 1) AS g, ARRAY(1e0, 2e0, 3e0) AS x).TRANSFORM(
        SELECT QUANTILE_DISC(x, 0.5e0) GROUP BY g
    ).UNWRAP_ONE()
;