HSQLDB计数每一天

Question

其表

id|date|somefield 

我需要得到的条目数为一年的每一天

select EXTRACT (DAY_OF_YEAR FROM date) as day, id from table 

工作正常

但是当我尝试

select EXTRACT (DAY_OF_YEAR FROM date) as day, count(*) from table 

失败

select count(*) from table group by EXTRACT (DAY_OF_YEAR FROM date) 

失败以及

Answer 1

您需要添加一个group by表达。这里有一些伪代码，我会在一会儿处理一个SqlFiddle。

select EXTRACT (DAY_OF_YEAR FROM date) as day, 
count(*) 
from table 
group by EXTRACT (DAY_OF_YEAR FROM date) 

从tableGROUP SQLFIDDLE（使用MySQL）http://sqlfiddle.com/#!2/42c9e/10