Native mogodb driver is used in node.js to limit the number of array returns. The same syntax works on the command line, but does not work in node
I want to do a paging query DEMO, wants to use db.collection.find ({"_ id": ObjectId (_ id)}, {"comments": {"$slice": 1}}), but the result of the query is still to query all the data of the array comments
the code is as follows
dbase
.collection("userInfo")
.findOne({ "_id": ObjectId(user_id)},{"comments":{"$slice":1}}, function(err, item) {
if (err) {
reject("faith");
throw new Error("");
} else {
let articalData = [];
for (let i = 0; i < item.comments.length; iPP) {
articalData.push({
_id: item.comments[i].id,
desc: item.comments[i].desc,
content: item.comments[i].content,
authorName: item.comments[i].name,
title: item.comments[i].title,
time: item.comments[i].time
});
}
let data = {
code: 0,
name: item.name,
articalData: articalData,
sumPage:item.comments.length%2?Number.parseInt(item.comments.length/2)+1:item.comments.length/2
};
resolve([dbase, data]);
}
});
did not report an error, but returned all the data and expected to see the data returned according to the restrictions.
