android - How to get week dates in SQLite database

Question

I am developing android application. One of my application table has "foo_date" as column name. and data type is TEXT. I have following data in my table

primary key  | foo_date  | foo_value
--------------------------------------
1             2013-3-1    100

2             2013-3-2    2

3             2013-3-4    100

4             2013-3-3    1000

my requirement is to get data for the current week(i.e. 2013-3-4 to 2013-3-10). When i write below query, i am getting all data except row # 3

select * from foo_tbl where foo_date between '2013-3-4' and '2013-3-10';

How do I write sqlite query so that it includes all data for current week?

Thansk Chintan

Answer 1

您的问题是您以无法轻松比较的格式存储了日期；字符1在前4，所以2013-3-10比较小于2013-3-4。

如文档所述，您应该使用 ISO 日期格式yyyy-mm-dd。使用恒定的字段大小，您可以使用具有有效字符串比较的查询：

SELECT * FROM foo WHERE foo_date BETWEEN '2013-03-04' AND '2013-03-10'

或使用日期函数来计算星期：

SELECT * FROM foo WHERE strftime('%W', foo_date) = '09'

Answer 2

首先，将日期存储为标准 sqlite 时间字符串格式（即 YYYY-MM-DD）。然后，你可以使用这个：

select * from foo where strftime('%W', foo_date) == strftime('%W', 'now')

选择与 now 具有相同周数的行。