Read Primitives — QUALIFY NTILE

Read Primitives benchmark · all Read Primitives queries

Find orders in top quartile per segment using NTILE

Representative SQL

Rendered for DataFusion with default parameters.

SELECT
  c_mktsegment,
  o_orderkey,
  o_totalprice,
  quartile
FROM (
  SELECT
    c_mktsegment,
    o_orderkey,
    o_totalprice,
    NTILE(4) OVER (PARTITION BY c_mktsegment ORDER BY o_totalprice, o_orderkey) AS quartile,
    NTILE(4) OVER (PARTITION BY c_mktsegment ORDER BY o_totalprice, o_orderkey) AS _w
  FROM orders AS o
  JOIN customer AS c
    ON o.o_custkey = c.c_custkey
  WHERE
    o_orderdate >= CAST('1995-01-01' AS DATE)
  ORDER BY
    c_mktsegment,
    o_totalprice DESC,
    o_orderkey DESC
) AS _t
WHERE
  _w = 4

Representative DataFrame

Expression family (Polars, PySpark, DataFusion), default parameters.

def qualify_ntile_expression_impl(ctx: DataFrameContext) -> Any:
    n = 4
    return (
        _orders_customer_since_1995_expr(ctx)
        .with_columns(
            ctx.window_ntile(
                n,
                order_by=[("o_totalprice", True), ("o_orderkey", True)],
                partition_by=["c_mktsegment"],
            ).alias("quartile")
        )
        .filter(ctx.col("quartile") == n)
        .select("c_mktsegment", "o_orderkey", "o_totalprice", "quartile")
        .sort(["c_mktsegment", "o_totalprice", "o_orderkey"], descending=[False, True, True])
    )

Get the exact query for your run

The blocks above are representative. To get the precise statement a specific platform runs at a specific scale, substitute your own values:

from benchbox import ReadPrimitives

bench = ReadPrimitives(scale_factor=0.01)            # your scale factor
queries = bench.get_queries(dialect="datafusion")   # your platform's dialect; drop dialect= for native SQL
print(queries['qualify_ntile'])

For the DataFrame form:

from benchbox.core.query_catalog import get_dataframe_render

print(get_dataframe_render('read_primitives', 'qualify_ntile', family="expression").source)  # or family="pandas"

Source

Query text: benchbox/core/read_primitives/queries.py