mongodb两层内嵌式数组怎么修改制定最内层的一个属性的值

Question

{
"_id" : ObjectId("549127427d3201f5086a711d"),
"_class" : "cn.togym.entity.SitePrice",
"siteId" : NumberLong(1122),
"date" : "2014.3.10",
"siteSlice" : [{
"sliceId" : 0,
"sliceName" : "场馆一",
"sliceIntroduction" : "阿斯达克减肥哈离开时记得发货了空间",
"siteSliceDetail" : [{
"SiteSliceDetailId" : 0,
"startTime" : "08:00",
"endTime" : "09:00",
"price" : 100.0,
"occupy" : 0
}, {
"SiteSliceDetailId" : 1,
"startTime" : "09:00",
"endTime" : "10:00",
"price" : 100.0,
"occupy" : 0
}, {
"SiteSliceDetailId" : 2,
"startTime" : "10:00",
"endTime" : "11:00",
"price" : 100.0,
"occupy" : 0
}]
}, {
"sliceId" : 1,
"sliceName" : "场馆一",
"sliceIntroduction" : "阿斯达克减肥哈离开时记得发货了空间",
"siteSliceDetail" : [{
"SiteSliceDetailId" : 0,
"startTime" : "08:00",
"endTime" : "09:00",
"price" : 100.0,
"occupy" : 0
}, {
"SiteSliceDetailId" : 1,
"startTime" : "09:00",
"endTime" : "10:00",
"price" : 100.0,
"occupy" : 0
}, {
"SiteSliceDetailId" : 2,
"startTime" : "10:00",
"endTime" : "11:00",
"price" : 100.0,
"occupy" : 0
}]
},
}],
"dateType" : "新年"
}
怎么修改sliceId=1并且startTime=08:00内的occupy的值。不知道他在数组内的下标