Question

我需要根据开始日期和结束日期生成一系列季度。我知道generate_series()，但它只适用于quarter：

SELECT * FROM generate_series('2008-01-01 00:00'::timestamp,'2009-01-01 12:00', '1 quarter');

是什么让季度如此特别？否则generate_series()适用于几乎所有事情，从微秒到千禧年：

select * from generate_series('2008-01-01 00:00'::timestamp,'2008-01-01 00:00:00.001', '1 microsecond');
select * from generate_series('2008-01-01 00:00'::timestamp,'2008-01-01 00:01', '1 second');
select * from generate_series('2008-01-01 00:00'::timestamp,'2008-01-01 01:00', '1 minute');
select * from generate_series('2008-01-01 00:00'::timestamp,'2008-01-01 12:00', '1 hour');
select * from generate_series('2008-01-01 00:00'::timestamp,'2009-01-01 12:00', '1 day');
select * from generate_series('2008-01-01 00:00'::timestamp,'2009-01-01 12:00', '1 week');
select * from generate_series('2008-01-01 00:00'::timestamp,'2009-01-01 12:00', '1 month');
select * from generate_series('2008-01-01 00:00'::timestamp,'2009-01-01 12:00', '1 year');
select * from generate_series('2008-01-01 00:00'::timestamp,'2009-01-01 12:00', '1 decade');
select * from generate_series('2008-01-01 00:00'::timestamp,'2009-01-01 12:00', '1 century');
select * from generate_series('2008-01-01 00:00'::timestamp,'2009-01-01 12:00', '1 millennium');

如果quarter无法使用，那么最好的其他选择是什么？现在，我有：

select 
   date_trunc('quarter',generate_series) gs 
from 
   generate_series('2008-01-01 00:00'::timestamp,'2009-01-01 12:00', '1 month') 
group by 
   gs
order by
   gs;

Answer 1

这不应该符合您的期望：

SELECT * FROM generate_series('2008-01-01 00:00'::timestamp,
                              '2009-01-01 12:00', '3 months');

结果：

   generate_series   
---------------------
 2008-01-01 00:00:00
 2008-04-01 00:00:00
 2008-07-01 00:00:00
 2008-10-01 00:00:00
 2009-01-01 00:00:00
(5 rows)

在Postgresql中生成一系列的季度

1 个答案: