exports.main = async (event, context) => {
return await db.collection("demoping").aggregate().match({
nsid:"989f4e215ecb612200340cad70da848c"
}).lookup({
from: 'demonews',
localField: 'nsid',
foreignField: '_id',
as: 'nsArr'
}).replaceRoot({
newRoot: $.mergeObjects([ $.arrayElemAt(['$nsArr', 0]), '$$ROOT' ])
}).sort({
"posttime":-1
})
.end();
}
这是我写了一个聚合，我想要将demonews里面素有的数据都拿过来，但是demoping里面出先了重复字段名称，那么怎么处理那？
用project
db.collection("demoping").aggregate().match({nsid:"989f4e215ecb612200340cad70da848c"}).project({content: 0,openid: 0}).lookup({from: 'demonews',localField: 'nsid',foreignField: '_id',as: 'nsArr'}).replaceRoot({newRoot: $.mergeObjects([ $.arrayElemAt(['$nsArr', 0]), '$$ROOT' ])}).sort({"posttime":-1}).end();