Question

我正在编写以下查询以按月计算销售率，并且我想确保它始终查看间隔：过去12个月的月初至月底。我已经尝试了以下方法，但是我不确定它是否需要使用本月的第一天和最后一天，我觉得可以用较短的查询来编写？

select 
datetrunc('month',date)
,count(id) filter (where status='sold' and (date between (datetrunc('month','current_date - interval '1 months')) and datetrunc('month', current_date) - Interval '1 days'))
/ count(id) filter (where date between (datetrunc('month','current_date - interval '1 months')) and datetrunc('month', current_date) - Interval '1 days') as Mar2020_Sales_Rate
,..... as Feb2020_Sales_Rate
,.
,.
,..... as Mar2019_Sales_Rate
from sales
group by 1;

Answer 1

这是我选择获取月1日和月底的方式，而不使用当前日期，而是使用数据中的（订单的）创建日期。请提出其他似乎更有效的查询，或者如果您认为此查询存在缺陷，请提出建议：

select distinct creation_date::date,
       (creation_date - Interval '1 months')::date as Minus_1M,
       (creation_date - Interval '2 months')::date as Minus_2M,
       (creation_date - Interval '3 months')::date as Minus_3M,
       ...
       (creation_date - Interval '12 months')::date as Minus_12M,
       extract('day' from creation_date) as Day_of_month,
       date_trunc('month', (creation_date::date - extract('day' from 
       creation_date)::int))::date as Beginning_of_month,
       creation_date::date - extract('day' from creation_date)::int as End_of_month
from order_data
order by 1 desc;

使用current_date获取过去12个月的月初和月末

1 个答案: