Meteor 对集合有不同的查询吗? [英] Does Meteor have a distinct query for collections?
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问题描述
我想在我的集合中返回不同的字段.我知道这些是 mongo 操作员的文档,但我对查询语言不够熟悉,无法了解如果这可能吗?
I'd like to return distinct fields in my collection. I know these are the docs for mongo operators, but I'm not familiar enough with the query language to know if this is possible?
Meteor.publish("distinctCollection", function() {
return Collection.find({ ... }, fields: { "myField": 1 });
});
推荐答案
Collection.find({}).distinct('myField', true);
要使用,将以下内容放入[project]/client/lib/a.js:
To use, put the following in [project]/client/lib/a.js:
LocalCollection.Cursor.prototype.distinct = function (key,random) {
var self = this;
if (self.db_objects === null)
self.db_objects = self._getRawObjects(true);
if (random)
self.db_objects = _.shuffle(self.db_objects);
if (self.reactive)
self._markAsReactive({ordered: true,
added: true,
removed: true,
changed: true,
moved: true});
var res = {};
_.each(self.db_objects,function(value){
if(!res[value[key]]){
res[value[key]] = value;
}
});
return _.values(res);
};
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