get Selected fields in .populate() waterline-postgresql .populate('fieldName',{select:[]})

问题

select query is not working in .populate() of waterline-postgresql.

Model.find(query).populate(assoc.alias,{select:['field1','field2']});

This is not working in waterline-postgresql adapter.

Is this not supported or Am I making any mistake?

回答1:

select is not supported in .populate(). You can see this github issue. In populate select is not working currently.

This is feature request and it is open issue. hope in next release waterline team will introduce this feature.

回答2:

Since there's no official way to do that I did some changes in order to have that. Maybe it's not the best way but it works.

User.find({ belongs_to: user.id })
.populate('person_id')
.exec(function findCB (err, usersFound)
{
    console.log(usersFound[0].toJSON())

    if (err)
    {
        return res.json(401, {error: err});
    }

    if (usersFound.length == 0)
    {
        return res.json(200, {message: 'No user asigned'});
    }
    else
    {
        // An array to store all the final user objects
        var asignedArray = [];

        for (index in usersFound)
        {
            var myObj = {},
                key,
                value;

            // Object in format {key: value}
            myObj['id'] = usersFound[index].id;
            myObj['fullname'] = usersFound[index].person_id.first_name + ' ' +
                                usersFound[index].person_id.second_name + ' ' +
                                usersFound[index].person_id.last_name;
            myObj['email'] = usersFound[index].email;
            myObj['job'] = usersFound[index].person_id.job;
            myObj['permission_level'] = usersFound[index].permission_level;

            // Adding the object to the main array
            asignedArray.push(myObj);
        }

        return res.json(200, {
            users: asignedArray
        });
    }
    });

I hope it could be useful for you.

来源：https://stackoverflow.com/questions/31292018/get-selected-fields-in-populate-waterline-postgresql-populatefieldname-s