grails - grails查询以获取一周中每一天的平均值

Question

我有一个grails域类，它看起来像这样:

class Answer {
String response
Integer score
Date created = new Date()
}         

如何进行查询以返回一周中每一天的平均分数？ ， 像这样 :

average for Mondays = 25
average for Tuesdays = 20
....
average for sundays = 10

Answer 1

这是对@ lucke84答案的补充，对他的方法做了很小的修改(以防丢失我对他的答案的编辑)

def summation = [
'monday': [],
'tuesday': [], 
'wednesday': [],
'thursday': [],
'friday': [],
'saturday': [],
'sunday': []
]


def answers = Answer.list() 
answers.each {
    def dateCreated = it.created[Calendar.DAY_OF_WEEK]

    switch (dateCreated) {
        case Calendar.MONDAY:
            summation.monday << it.score     
            break
        case Calendar.TUESDAY:
            summation.tuesday << it.score
            break
        case Calendar.WEDNESDAY:
            summation.wednesday << it.score
            break
        case Calendar.THURSDAY:
            summation.thursday << it.score
            break
        case Calendar.FRIDAY:
            summation.friday << it.score   
            break
        case Calendar.SATURDAY:
            summation.saturday << it.score
            break
        case Calendar.SUNDAY:
            summation.sunday << it.score
            break
    } ​ 
}

def averages = [:]
averages.monday = (summation['monday'].sum())?.divide(summation['monday'].size())
//So on and So forth.

请注意， .list()将带回 Answer的所有行，这可能会影响性能。在这种情况下，您可以使用 findAll并根据需要传递 pagination参数。