psql 列转行

全栈程序员站长

发布于 2022-06-24 21:32:50

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发布于 2022-06-24 21:32:50

文章被收录于专栏：全栈程序员必看全栈程序员必看

大家好，又见面了，我是你们的朋友全栈君。

需求

学生成绩表

创建表初始化

CREATE TABLE public.test ( name VARCHAR(20), score FLOAT, total_availability FLOAT, shelf_availability FLOAT );
INSERT INTO public.test (name, score, total_availability, shelf_availability) VALUES ('A', 1, 1.1, 1.2);
INSERT INTO public.test (name, score, total_availability, shelf_availability) VALUES ('B', 3, 2.1, 2.2);
INSERT INTO public.test (name, score, total_availability, shelf_availability) VALUES ('C', 6, 3.3, 3.4);
INSERT INTO public.test (name, score, total_availability, shelf_availability) VALUES ('D', 10, 4.1, 4.2);

SELECT * FROM public.test;

行转列

SELECT name, score, unnest(ARRAY ['total_availability' :: TEXT, 'shelf_availability' :: TEXT]) AS kpi_details, unnest( ARRAY [public.test.total_availability :: NUMERIC(30, 16), public.test.shelf_availability :: NUMERIC(30, 16)]) AS value FROM public.test;