How to Set “OR”, “AND”, “SORT”, “LIMIT” Operator in Mongoose + MongoDB

10/11/202010/13/2020mongodbmongodb,mongoose

Mongoose is Object – Database modeling library with mongodb and node.js.

How to set “OR" and “AND" query in find methods?

You can set “OR" operator in the find method like the following syntax.

$or: [{condition1},{condition2}]

Example 1. Use “$or" operator.

pets = await Pet.find({
      $or: [
        { email: user.email },
        { ownerId: authUserId },
      ],
    });

Example 2. Use “$or" and “$and" operator.

    pets = await Pet.findOne({
      $and: [
        {
          $or: [
            { email: user.email },
            { ownerId: authUserId },
          ],
        },
        { _id: petId },
      ],
    });

How to Use “SORT" and “LIMIT"

Example 3. Use “sort()" and “limit()“

feds = await Feed.find({ petId: 'PETID' }).sort({ date: -1 }).limit(5);

Delete Array Elements in Document with Mongoose

To use “$pull" or “$pullAll" is recommended.

Example 4. Use $pullAll

await User.updateOne({ authUserId: 'user001' },{ $pullAll: { pets: [petId] } });