Math

LOG

DuckDB

Menghitung logaritma dari sebuah angka. Bisa natural log (ln) atau dengan base tertentu.

Tipe hasil: DOUBLEDiperbarui: 6 Jan 2026

Syntax

SQL

LOG(number) | LOG(base, number)

Parameter

numberDOUBLEwajib

Angka yang akan dihitung logaritmanya (harus > 0)

baseDOUBLEopsional

Basis logaritma. Optional, default adalah e (natural log)

Contoh Penggunaan

Berbagai Basis Logaritma

SQL

1 SELECT
2   value,
3   LOG(value) as natural_log,
4   LOG(10, value) as log_base_10,
5   LOG(2, value) as log_base_2
6 FROM (SELECT unnest([1, 10, 100, 1000]) as value);

Membandingkan logaritma dengan berbagai basis.

Hasil

value	natural_log	log_base_10	log_base_2
1	0	0	0
10	2.303	1	3.322
100	4.605	2	6.644
1000	6.908	3	9.966

Growth Rate Analysis

SQL

1 SELECT
2   year,
3   revenue,
4   LOG(revenue / LAG(revenue) OVER (ORDER BY year)) as log_growth
5 FROM company_revenue
6 WHERE year >= 2020;

Menghitung log growth rate untuk analisis pertumbuhan.

Hasil

year	revenue	log_growth
2020	1000000000	NULL
2021	1200000000	0.182
2022	1500000000	0.223
2023	2000000000	0.288

Logarithmic Scaling

SQL

1 SELECT
2   category,
3   total_sales,
4   ROUND(LOG(10, total_sales), 2) as log_scale,
5   ROUND(LOG(10, total_sales) * 10, 0) as score
6 FROM category_sales
7 ORDER BY total_sales DESC;

Menggunakan log scale untuk membuat skor yang lebih terdistribusi.

Hasil

category	total_sales	log_scale	score
Electronics	5000000000	9.70	97
Clothing	500000000	8.70	87
Books	50000000	7.70	77

Fungsi Terkait

EXPLNLOG10LOG2

Kembali ke DuckDB Functions

1	SELECT
2	value,
3	LOG(value) as natural_log,
4	LOG(10, value) as log_base_10,
5	LOG(2, value) as log_base_2
6	FROM (SELECT unnest([1, 10, 100, 1000]) as value);

1	SELECT
2	year,
3	revenue,
4	LOG(revenue / LAG(revenue) OVER (ORDER BY year)) as log_growth
5	FROM company_revenue
6	WHERE year >= 2020;

1	SELECT
2	category,
3	total_sales,
4	ROUND(LOG(10, total_sales), 2) as log_scale,
5	ROUND(LOG(10, total_sales) * 10, 0) as score
6	FROM category_sales
7	ORDER BY total_sales DESC;