一尘不染

如何在PostgreSQL中按周分组

sql

我有一个数据库表,commits其中包含以下列:

id | author_name | author_email | author_date(时间戳)| total_lines

样本内容为:

1 | abc | abc@xyz.com | 2013-03-24 15:32:49 | 1234
2 | abc | abc@xyz.com | 2013-03-27 15:32:49 | 534
3 | abc | abc@xyz.com | 2014-05-24 15:32:49 | 2344
4 | abc | abc@xyz.com | 2014-05-28 15:32:49 | 7623

我想得到如下结果:

id | name | week | commits
1  | abc  | 1    | 2
2  | abc  | 2    | 0

我在网上搜索了类似的解决方案,但找不到任何有用的解决方案。

我试过这个查询:

SELECT      date_part('week', author_date::date) AS weekly,
        COUNT(author_email)           
FROM        commits
GROUP BY    weekly
ORDER BY weekly

但这不是正确的结果。


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2021-03-17

共1个答案

一尘不染

如果您有多个年份,则也应该考虑年份。一种方法是:

SELECT date_part('year', author_date::date) as year,
       date_part('week', author_date::date) AS weekly,
       COUNT(author_email)           
FROM commits
GROUP BY year, weekly
ORDER BY year, weekly;

一种更自然的写方法是date_trunc()

SELECT date_trunc('week', author_date::date) AS weekly,
       COUNT(author_email)           
FROM commits
GROUP BY weekly
ORDER BY weekly;
2021-03-17