Aggregate

PERCENTILE_DISC

PostgreSQL

Menghitung percentile diskrit dari data. Mengembalikan nilai aktual dari dataset (tidak diinterpolasi). Berbeda dengan PERCENTILE_CONT yang menginterpolasi.

Tipe hasil: same as input

Syntax

SQL

PERCENTILE_DISC(fraction) WITHIN GROUP (ORDER BY expression)

Parameter

fractionnumericwajib

Nilai percentile antara 0 dan 1

expressionany orderablewajib

Kolom yang akan dihitung percentilenya

Contoh Penggunaan

Median Diskrit

SQL

1 SELECT 
2   PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY rating) AS median_rating
3 FROM reviews;

Menghitung median rating (nilai aktual dari data).

Hasil

median_rating
4

Perbandingan CONT vs DISC

SQL

1 SELECT 
2   PERCENTILE_CONT(0.5) WITHIN GROUP (ORDER BY score) AS cont_median,
3   PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY score) AS disc_median
4 FROM (
5   VALUES (1), (2), (3), (4)
6 ) AS t(score);

CONT menginterpolasi (2.5), DISC mengambil nilai aktual (2).

Hasil

cont_median	disc_median
2.5	2

Top 10% Performers

SQL

1 SELECT *
2 FROM employees
3 WHERE performance_score >= (
4   SELECT PERCENTILE_DISC(0.9) 
5   WITHIN GROUP (ORDER BY performance_score)
6   FROM employees
7 );

Mencari karyawan dengan skor di top 10%.

Fungsi Equivalen di Database Lain

PERCENTILE_DISC

Snowflake

PERCENTILE_DISC

BigQuery

Fungsi Terkait

STDDEVVARIANCECORRCOVAR_POPCOVAR_SAMPPERCENTILE_CONTMODE

Kembali ke PostgreSQL Functions

1	SELECT
2	PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY rating) AS median_rating
3	FROM reviews;

1	SELECT
2	PERCENTILE_CONT(0.5) WITHIN GROUP (ORDER BY score) AS cont_median,
3	PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY score) AS disc_median
4	FROM (
5	VALUES (1), (2), (3), (4)
6	) AS t(score);

1	SELECT *
2	FROM employees
3	WHERE performance_score >= (
4	SELECT PERCENTILE_DISC(0.9)
5	WITHIN GROUP (ORDER BY performance_score)
6	FROM employees
7	);