在SQLite中按月分组

Question

我有一个包含事务的SQLite数据库,每个事务都有价格和transDate.

我想检索按月分组的事务总和.检索到的记录应如下所示:

Price    month
230        2
500        3
400        4

Answer 1

当你按月分组时,它总是很好,它也应该检查YEAR

select SUM(transaction) as Price, 
       DATE_FORMAT(transDate, "%m-%Y") as 'month-year' 
       from transaction group by DATE_FORMAT(transDate, "%m-%Y");

FOR SQLITE

select SUM(transaction) as Price, 
       strftime("%m-%Y", transDate) as 'month-year' 
       from transaction group by strftime("%m-%Y", transDate);

Answer 2

您可以在月初分组：

select  date(DateColumn, 'start of month')
,       sum(TransactionValueColumn)
from    YourTable
group by 
        date(DateColumn, 'start of month')