大橙子网站建设,新征程启航

为企业提供网站建设、域名注册、服务器等服务

postgresql中如何实现groupbyrange

小编给大家分享一下postgresql中如何实现group by range,相信大部分人都还不怎么了解,因此分享这篇文章给大家参考一下,希望大家阅读完这篇文章后大有收获,下面让我们一起去了解一下吧!

创新互联建站是一家专业提供义马企业网站建设,专注与做网站、成都网站设计、H5响应式网站、小程序制作等业务。10年已为义马众多企业、政府机构等服务。创新互联专业的建站公司优惠进行中。

  1. 建立测试表

testdb=# CREATE TEMP TABLE team (
id serial,
name text,
birth_year integer,
salary integer
);

  1. 插入记录

testdb=# INSERT INTO team (name, birth_year, salary)
VALUES ('Gabriel', 1970, 44000),
('Tom', 1972, 36000),
('Bill', 1978, 39500),
('Bob', 1980, 29000),
('Roger', 1976, 26800),
('Lucas', 1965, 56900),
('Jerome', 1984, 33500),
('Andrew', 1992, 41600),
('John', 1991, 40000),
('Paul', 1964, 39400),
('Richard', 1986, 23000),
('Joseph', 1988, 87000),
('Jason', 1990, 55000);

  1. 查询结果

testdb=# WITH series AS (  
SELECT generate_series(1950, 2000, 10) AS time_start -- 1950 = min, 2010 = max, 10 = 10 year interval
), range AS (
SELECT time_start, (time_start + 9) AS time_end FROM series -- 9 = interval (10 years) minus 1
)
SELECT time_start, time_end,
(SELECT count(*) FROM team WHERE birth_year BETWEEN time_start AND time_end) as team_members,
round((SELECT AVG(salary) FROM team WHERE birth_year BETWEEN time_start AND time_end), 2) as salary_avg,
(SELECT MIN(salary) FROM team WHERE birth_year BETWEEN time_start AND time_end) as salary_min,
(SELECT MAX(salary) FROM team WHERE birth_year BETWEEN time_start AND time_end) as salary_max
FROM range;

输出结果:

time_start | time_end | team_members | salary_avg | salary_min | salary_max
------------+----------+--------------+------------+------------+------------
1950 |     1959 |            0 |            |            |          
1960 |     1969 |            2 |   48150.00 |      39400 |      56900
1970 |     1979 |            4 |   36575.00 |      26800 |      44000
1980 |     1989 |            4 |   43125.00 |      23000 |      87000
1990 |     1999 |            3 |   45533.33 |      40000 |      55000
2000 |     2009 |            0 |            |            |          
(6 rows)

testdb=#

以上是“postgresql中如何实现group by range”这篇文章的所有内容,感谢各位的阅读!相信大家都有了一定的了解,希望分享的内容对大家有所帮助,如果还想学习更多知识,欢迎关注创新互联行业资讯频道!


当前文章:postgresql中如何实现groupbyrange
网站URL:http://dzwzjz.com/article/gjjsih.html
在线咨询
服务热线
服务热线:028-86922220
TOP