find multiple document ascending with limit 1 mongoose - node.js

Question

I am new to Mongodb.
This is what i have tried
var fdevices = mongoose.model('fdevices', dataModelSchema);
var DPMPow = fdevices.findOne({ "Data": { $regex: /DPMPow_P01/i }
}).sort({ field: 'asc', _id: -1 });
var DPMAmp = fdevices.findOne({ "Data": { $regex: /DPMAmp_P01/i }
}).sort({ field: 'asc', _id: -1 });
var DPMkWh = fdevices.findOne({ "Data": { $regex: /DPMkWh_P01/i }
}).sort({ field: 'asc', _id: -1 });
var MxPeak = fdevices.findOne({ "Data": { $regex: /MxPeak_P01/i }
}).sort({ field: 'asc', _id: -1 });
var MPPeak = fdevices.findOne({ "Data": { $regex: /MPPeak_P01/i }
}).sort({ field: 'asc', _id: -1 });
function getReady() {
async.series([
function (callback) {
DPMPow.exec(function (err, res) {
callback(null, res);
})
},
function (callback) {
DPMAmp.exec(function (err, res) {
callback(null, res);
});
},
function (callback) {
DPMkWh.exec(function (err, res) {
callback(null, res);
})
},
function (callback) {
MxPeak.exec(function (err, res) {
callback(null, res);
})
}, function (callback) {
MPPeak.exec(function (err, res) {
callback(null, res);
}) ], function (error, results) {
console.log(results);
}
);
}
above method works for me but its very slow. is there a way i can design single query and get same result instead of queering data one by one.
In my collection i have single field called "Data" and my collection contains more than a one million document.

Answer 1

var fdevices = mongoose.model('fdevices', dataModelSchema);
var DPMPow = fdevices.find({
$or: [{
"Data": { $regex: /DPMPow/i }
}, {
"Data": { $regex: /DPMAmp/i }
}, {
"Data": { $regex: /DPMkWh/i }
}, {
"Data": { $regex: /MxPeak/i }
}, {
"Data": { $regex: /MPPeak/i }
}]
}).sort({ field: 'asc', _id: -1 });
DPMPow.exec(function(err, res) {
//Now travese thru all the records, when ever you find the unique pattren of
//data remove all the instances of that particular pattren
});