Mongo C# Driver CRUD CheatSheet

Example.cs

//Read
//BsonDocument
var collection = db.GetCollection<BsonDocument>("people");
var builder = Builders<BsonDocument>.Filter;
    
//Note that the '&' '!' '|' operators are overloaded when used in the FilterBuilder
var filter = builder.Lt("Age", 33) & !builder.Eq("Name", "Ericsson");
var list = await collection.Find(filter).ToListAsync();
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//Strongly Typed
var collection = db.GetCollection<People>("people");
var list = await collection.Find(x => x.Age < 30 && x.Name != "Ericsson")
    .ToListAsync();


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//Sorting
var collection = db.GetCollection<People>("people");
var list = await collection.Find(x => x.Age < 30 && x.Name != "Ericsson")
    .SortBy(x => x.Age)
    .ThenByDescending(x => x.Name)
    .ToListAsync();

await collection.Find(builder.Eq("type", "homework"))
                .Sort(Builders<BsonDocument>.Sort.Ascending("student_id").Ascending("score")); //do some async operation here

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//Projections
var collection = db.GetCollection<People>("people");
var list = await collection.Find(new BsonDocument())
    .Project(x => x.Name)
    .ToListAsync();

//Everything except the calculation will be handeld server side. The calculation
list = await collection.Find(new BsonDocument())
    .Project(x => new { x.Name, Calcage = x.Age + 20 })
    .ToListAsync();

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//Replace & Updates
var collection = db.GetCollection<Widget>("widgets");
var result = await collection.ReplaceOneAsync(
    new BsonDocument("x", 10), //Where x is 10
    new BsonDocument("x", 30), //x will be set to thirty
    new UpdateOptions { IsUpsert = true}); //If with value 10 is non-existing x with value 30 will be inserted
//Alternative
var result = await collection.ReplaceOneAsync(
    Builders<BsonDocument>.Filter.Eq("x", 10),
    Builders<BsonDocument>.Filter.Eq("x", 30),
    new UpdateOptions { IsUpsert = true});

//Update
//Increments the specified document where x is 5 to be 6
var result = await collection.UpdateOneAsync(
    Builders<BsonDocument>.Filter.Eq("x", 5),
    Builders<BsonDocument>.Update.Inc("x", 1));
//Increments the specified documents where x is greater then 5 by 1 
var result = await collection.UpdateManyAsync(
    Builders<BsonDocument>.Filter.Gt("x", 5),
    Builders<BsonDocument>.Update.Inc("x", 1));

//Strongly Typed Alternative 1
var result = await collection.UpdateManyAsync(
    Builders<Person>.Filter.Gt(x => x.X, 5),
    Builders<BsonDocument>.Update.Inc(x => x.X, 1));

//Strongly Typed Alternative 2
var result = await collection.UpdateManyAsync(
    x => x.X > 5, //This syntax is availabe for filters only
    Builders<BsonDocument>.Update.Inc(x => x.X, 1).Set("Y", 20)); 
//Sets a new field on the document - //will be problems when we read to POCOs

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//Delete
var collection = db.GetCollection<Widget>("widgets");
var result = await collection.DeleteOneAsync(x => x.X > 5);
var result = await collection.DeleteManyAsync(x => x.X > 5);
    
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//FindAndUpdate - Same for FindAndDelete
var collection = db.GetCollection<Widget>("widgets");
//Returns the modified document before modification
var result = await collection.FindOneAndUpdateAsync(
    x => x.X > 5,
    Builders<Widget>.Update.Inc(x => x.X, 1));

var result = await collection.FindOneAndUpdateAsync<Widget>(
    x => x.X > 5,
    Builders<Widget>.Update.Inc(x => x.X, 1),
    new FindOneAndUpdateOptions<Widget, Widget> //Second Widghet T parameter says what we wont to work with, we could enter a projection here
    {
        ReturnDocument = ReturnDocument.After, //Returns the document after modification
        Sort = Builders<Widget>.Sort.Descending(x => x.X) //Takes the first document matching the filter and increments
    });

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//BulkWriter
var collection = db.GetCollection<Widget>("widgets");
//Performs all operation in one turn to the database
var result = collection.BulkWriteAsync(new WriteModel<BsonDocument>[]
{
    new DeleteOneModel<BsonDocument>("{x: 5}"),
    new DeleteOneModel<BsonDocument>("{x: 7}"),
    new UpdateManyModel<BsonDocument>("{x: {$lt: 7}}", {"$inc: {x: 1}}")
});