如何在 Mongoose/MongoDB 中执行 $or 查询？

Question

I need to get a variety of items in my MongoDB collection based on an $or statement.

Following these official docs the query I have constructed looks acceptable, yet the first $gt statement is not being fulfilled. It is returning items that have a quantity equal to zero.

let query = {};

query.$or = [ { 'quantity': { $gt: 0 } }, { type: { $in: [ITEM_TYPE_A, ITEM_TYPE_B] } }];

db.Items.find(query).then( res => res)

Could it be the dot syntax appending a new key/value pair to the query object? Unfortunetly this query is just one of many that get appended to the query object based on if statements. Ex. if (something) query.field = value

Answer 1

I can't figure out why, but using the Object.assign method fixed my query.

Instead of:

query.$or = [ { 'quantity': { $gt: 0 } }, { type: { $in: [ITEM_TYPE_A, ITEM_TYPE_B] } }]

I did:

query = Object.assign({}, query, { $or: { 'quantity': { $gt: 0 } }, { type: { $in: [ITEM_TYPE_A, ITEM_TYPE_B]}

Answer 2

you can use one of following

let query = {};

query = {...query,$or:[ { 'quantity': { $gt: 0 } }, { type: { $in: [ITEM_TYPE_A, ITEM_TYPE_B] } }]};

or

query = Object.assign({}, query, { $or: [ { 'quantity': { $gt: 0 } }, { type: { $in: [ITEM_TYPE_A, ITEM_TYPE_B] } }]});

or

query["$or"] = [ { 'quantity': { $gt: 0 } }, { type: { $in: [ITEM_TYPE_A, ITEM_TYPE_B] } }];