CRUD Operations

This document deals with basic Create, Read, Update and Delete operations using the mongo shell.

📖 Read more about CRUD operations.

Create Operations

A MongoDB database is made up of 1 or more collections which are in turn made up of 1 or more documents. A document has a key: value structure, similar to JSON objects. In the following exercises, we'll learn how to insert documents using the following methods:

insertOne()
insertMany()

Exercise 1 💻

Verify what database you are currently using (should be test, this is the default.) MongoDB makes this a super easy step. From the Mongo-Shell type db and hit Enter, the output is the current working database.

query: javascript db

Let's create a new database called employee_db.
```
use employee_db
```

➡️ Note that use creates a new database, if one does not already exist.

Next, let's create a collection called employee_info.
```
db.createCollection("employee_info")
```
Let's confirm that the collection was successfully created.
```
show collections
```

➡️ Similarly, you can also use show dbs to obtain a list of the all the databases.

Let's try to insert some data into our collection.

You are used to seeing data in a tabular format due to the relational database structure. So let's start with a table as seen below and then convert it into a JSON object that can be inserted into our collection.

fname	lname	salary	departments	hiredate
john	doe	70000	sales, admin	2018-08-29

Converting this table into an object, a set of key:value pairs surrounded by {} looks like this:

    {
	"fname": "john",
        "lname": "doe",
        "salary": 70000,
        "departments": ["sales", "admin"],
        "hiredate": "2018-08-29"
    }

Now that we have our JSON object, let's insert it into our collection.

query:

    db.employee_info.insertOne({
        "fname": "john", 
        "lname": "doe", 
        "salary": 70000, 
        "departments": ["sales", "admin"], 
        "hiredate": "2018-08-29"})

result:

    {
        "acknowledged" : true,
        "insertedId" : ObjectId("5d8e6f9ccaa4f8ddbe27296f")
    }

The response to this query is a document in itself as seen below. "acknowldeged": true means we the insert was successful. Also note the Object ID which is the unique identifier for this document. Every document has its own unique _id. It is not necessary to specify _id in the query in which case, MongoDB will automatically add one to the document.

💡 Letting Mongo take care of your _id field is a good idea. Mongo will never try to assign a duplicate value to this field, sometimes we make mistakes and may try to do that. Mongo is pretty relaxed and sometimes doesn't stop us from doing reckless things such as assigning the same _id to more than one Object. If you need control over an id field for you document consider creating one instead of overwriting the object id. Exercise 2 💻

HR has sent over new employee information. Spend 5 minutes ⏰ to insert the new data into the employee_info collection.

The data is first shown in tabular format followed by JSON object format to ease you into thinking about data non-relationally.

empno	fname	lname	role	departments
1	charlie	rodgers	manager	sales, marketing
2	sunil	chakraborty	team lead	marketing, finance
3	sally	jones	team lead	hr, admin
4	ben	bradley	manager	legal
5	radha	desai	worker
6	shruti	patel	worker
7	mahesh	iyer	manager

{
  "empno": 1,
  "fname": "charlie",
  "lname": "rodgers",
  "role": "manager",
  "departments": ["sales", "marketing"]
},
{
  "empno": 2,
  "fname": "sunil",
  "lname": "chakraborty",
  "role": "team lead",
  "departments": ["marketing", "finance"]
},
{
  "empno": 3,
  "fname": "sally",
  "lname": "jones",
  "role": "team lead",
  "departments": ["hr", "admin"]
},
{
  "empno": 4,
  "fname": "ben",
  "lname": "bradley",
  "role": "manager",
  "departments": ["legal"]
},
{
  "empno": 5,
  "fname": "radha",
  "lname": "desai",
  "role": "worker"
},
{
  "empno": 6,
  "fname": "shruti",
  "lname": "patel",
  "role": "worker"
},
{
  "empno": 7,
  "fname": "mahesh",
  "lname": "iyer",
  "role": "manager"
}

➡️ You might be wondering whether the insert will work, given that some of the keys (field names) are different from the document we inserted earlier and not all records have data in every field. Here lies the beauty of MongoDB!!! Unlike relational databases, the same keys (field names) do not have to be present in all documents of the collection. Also, if data isn't present in a particular field, that field simply gets omitted from a given document. 👏

💡 How many of you inserted the documents one by one?

It's not wrong but the more efficient way of inserting multiple documents is to use insertMany(). Simply replace insertOne() in the query above with insertMany().

➡️ Keep in mind that insertMany() takes an array as input so enlcose all your documents in [] as shown in the query below.

query:

db.employee_info.insertMany([
    {
    "empno": 1, 
    "fname": "charlie", 
    "lname": "rodgers", 
    "role": "manager", 
    "departments": ["sales", "marketing"]
    }, 
    {
    "empno": 2, 
    "fname": "sunil", 
    "lname": "chakraborty", 
    "role": "team lead", 
    "departments": ["marketing", "finance"]
    }, 
    {"empno": 3, 
    "fname": "sally", 
    "lname": "jones", 
    "role": "team lead", 
    "departments": ["hr", "admin"]
    }, 
    {
    "empno": 4, 
    "fname": "ben", 
    "lname": "bradley", 
    "role": "manager", 
    "departments": ["legal"]
    }, 
    {
    "empno": 5, 
    "fname": "radha", 
    "lname": "desai", 
    "role": "worker"
    }, 
    {
    "empno": 6, 
    "fname": "shruti", 
    "lname": "patel", 
    "role": "worker"
    }, 
    {
    "empno": 7, 
    "fname": "mahesh", 
    "lname": "iyer", 
    "role": "manager"
    }
])

Exercise 3 💻

You've got some more interesting employees! Spend 10 minutes ⏰ converting the following table to JSON and inserting it into our employee_info collection.

name	title	interesting fact	address
Harry Potter	Wizard	I kicked the sh*t out of Voldemort!	Hogwarts castle
Groot	Superhero	I can only say 3 words in this order: 'I am Groot'!	Planet X
Pikachu	Electric type pokemon	Want to see my ThuderBolt and Quick Attack?!	Pallet Town

Read Operations

⚠️ Before we dive into our Read operations, make sure you can access the pokemon-cards collection. Use commands like show dbs, use <db name>, show collections to correctly naviagte to the intended collection.

For any of you who haven't played the Pokemon card game, I highly recommend it! Also, once you learn enough MongoDB querying, you can analyze this database to find out which cards are the most powerful to include in your deck! 🎉

Counting records

Exercise 4 💻

Let's start with a simple count() operation in order to count the number of documents in the collection.

📖 Read More about the count() method.

query:

db.cards.count()

➡️ count() returns the total of all documents, which means duplicate documents will be counted.

To get a count of unique values in a given field, replace count() with distinct() and enter a field value of your choice as the first argument.

query:

db.cards.distinct("hp")

➡️ hp stands for Hit Points and is the amount of damage a Pokemon can take.

Filtering on a single field

In order to filter data, add a parameter as the first argument to the count() method. Parameters exist as objects, and are therefore key:value pairs.

In the query below, hp is the key and 250 is the value.

Exercise 5 💻

We definitely want to have high hp Pokemon in our winning deck so let's find how many of those we have.

query:

db.cards.count({"hp": "250"})

Filtering on multiple fields

Adding another parameter using the , operator ANDs the filters and returns the matching results.

Exercise 6 💻

There are various subtype of Pokemon cards. You can take a look by running the distinct() query against this field. One of those subtype is 'GX' which is a super strong Pokemon card that comes with 💪 attacks. Let's find out how many 'GX' cards have an hp of 250.

query:

db.cards.count({"hp":"250", "subtype":"GX"})

➡️ The documents returned are only those where BOTH parameters match.

Using the "find()" method

To display an entire document, use the find() method. When using find() with no additional parameters, every document in the database will be returned. Usually you will want to add parameters to find() in order to filter your results. Remember that , is an AND operator.

📖 Read More about the find() method.

Exercise 7 💻

Let's take a look at what the powerful cards we came across in the previous exercise actually look like!

query:

db.cards.find({"hp":"250", "subtype":"GX"})

result: (Only a part of the output has been shown.)

{ "_id" : ObjectId("5c20177bf2e24cfe71961322"), "id" : "sm2-157", "name" : "Metagross-GX", "nationalPokedexNumber" : 376, "imageUrl" : "https://images.pokemontcg.io/sm2/157.png", "imageUrlHiRes" : "https://images.pokemontcg.io/sm2/157_hires.png", "types" : [ "Metal" ], "supertype" : "Pokemon", "subtype" : "GX", "evolvesFrom" : "Metang", "ability" : { "name" : "Geotech System", "text" : "Once during your turn (before your attack), you may attach a Psychic or Metal Energy card from your discard pile to your Active Pokemon.", "type" : "Ability" }, "hp" : "250", "retreatCost" : [ "Colorless", "Colorless", "Colorless" ], "convertedRetreatCost" : 3, "number" : "157", "artist" : "5ban Graphics", "rarity" : "Rare Secret", "series" : "Sun & Moon", "set" : "Guardians Rising", "setCode" : "sm2", "text" : [ "When your Pokemon-GX is Knocked Out, your opponent takes 2 Prize cards." ], "attacks" : [ { "cost" : [ "Metal", "Metal", "Colorless" ], "name" : "Giga Hammer", "text" : "This Pokemon can't use Giga Hammer during your next turn.", "damage" : "150", "convertedEnergyCost" : 3 }, { "cost" : [ "Colorless" ], "name" : "Algorithm-GX", "text" : "Search your deck for up to 5 cards and put them into your hand. Then, shuffle your deck. (You can't use more than 1 GX attack in a game.)", "damage" : "", "convertedEnergyCost" : 1 } ], "resistances" : [ { "type" : "Psychic", "value" : "-20" } ], "weaknesses" : [ { "type" : "Fire", "value" : "×2" } ] }

As you can see, the output contains the entire document in a single line. This makes it hard to discern the layout of the document. We'll cover easy document parsing in the next exercise.

Exercise 8 💻

Like JavaScript, the MongoDB query language can chain methods together to refine the output of your queries. Chaining happens by placing a . between method names.

Let's chain the pretty() method to the find() method for a prettier print of the output where each new field is written on a new line.

query:

db.cards.find({"hp":"250", "subtype":"GX"}).pretty()

result: (Only a part of the output has been shown.)

{
	"_id" : ObjectId("5c20177bf2e24cfe71961322"),
	"id" : "sm2-157",
	"name" : "Metagross-GX",
	"nationalPokedexNumber" : 376,
	"imageUrl" : "https://images.pokemontcg.io/sm2/157.png",
	"imageUrlHiRes" : "https://images.pokemontcg.io/sm2/157_hires.png",
	"types" : [
		"Metal"
	],
	"supertype" : "Pokemon",
	"subtype" : "GX",
	"evolvesFrom" : "Metang",
	"ability" : {
		"name" : "Geotech System",
		"text" : "Once during your turn (before your attack), you may attach a Psychic or Metal Energy card from your discard pile to your Active Pokemon.",
		"type" : "Ability"
	},
	"hp" : "250",
	"retreatCost" : [
		"Colorless",
		"Colorless",
		"Colorless"
	],
	"convertedRetreatCost" : 3,
	"number" : "157",
	"artist" : "5ban Graphics",
	"rarity" : "Rare Secret",
	"series" : "Sun & Moon",
	"set" : "Guardians Rising",
	"setCode" : "sm2",
	"text" : [
		"When your Pokemon-GX is Knocked Out, your opponent takes 2 Prize cards."
	],
	"attacks" : [
		{
			"cost" : [
				"Metal",
				"Metal",
				"Colorless"
			],
			"name" : "Giga Hammer",
			"text" : "This Pokemon can't use Giga Hammer during your next turn.",
			"damage" : "150",
			"convertedEnergyCost" : 3
		},
		{
			"cost" : [
				"Colorless"
			],
			"name" : "Algorithm-GX",
			"text" : "Search your deck for up to 5 cards and put them into your hand. Then, shuffle your deck. (You can't use more than 1 GX attack in a game.)",
			"damage" : "",
			"convertedEnergyCost" : 1
		}
	],
	"resistances" : [
		{
			"type" : "Psychic",
			"value" : "-20"
		}
	],
	"weaknesses" : [
		{
			"type" : "Fire",
			"value" : "×2"
		}
	]
}

Much nicer on our 👀 !

Filtering embedded documents

Driving down the hierarchy in documents can be done using the dot notation.

Exercise 9 💻

Since we're on a quest to build a solid Pokemon card deck, the most logical next question to ask would be "How much energy do these 💪 attacks take?" There are various energy cards in the Pokemon world - 🔥, water, and lightning to name a few. We're interested in attacks that cost 'Colorless' energy since we can use any other energy types in place of 'Colorless' in such attacks.

query:

db.cards.find({"hp":"250", "subtype": "GX", "attacks.cost": "Colorless"}).pretty()

Filtering array values

When it comes to matching on array values, we can match in 3 ways:

the entire array

Exercise 10 💻

What's better than one 'Colorless' attacks.cost? Two 'Colorless' attacks.cost!!! 😛

What I mean to say is, let's build on our previous query and find out if there are any cards that require only 2 'Colorless' energy to launch their attack!

query:

db.cards.find({"hp":"250", "subtype": "GX", "attacks.cost": ["Colorless", "Colorless"]}).pretty()

result: (Only a part of the output is shown.)

{
	"_id" : ObjectId("5c20177bf2e24cfe719626e2"),
	"id" : "smp-SM39",
	"name" : "Primarina-GX",
	"nationalPokedexNumber" : 730,
	"imageUrl" : "https://images.pokemontcg.io/smp/SM39.png",
	"imageUrlHiRes" : "https://images.pokemontcg.io/smp/SM39_hires.png",
	"types" : [
		"Water"
	],
	"supertype" : "Pokemon",
	"subtype" : "GX",
	"evolvesFrom" : "Brionne",
	"hp" : "250",
	"retreatCost" : [
		"Colorless",
		"Colorless"
	],
	"convertedRetreatCost" : 2,
	"number" : "SM39",
	"artist" : "5ban Graphics",
	"rarity" : "",
	"series" : "Sun & Moon",
	"set" : "SM Black Star Promos",
	"setCode" : "smp",
	"text" : [
		"When your Pokemon-GX is Knocked Out, your opponent takes 2 Prize cards."
	],
	"attacks" : [
		{
			"cost" : [
				"Colorless",
				"Colorless"
			],
			"name" : "Bubble Beat",
			"text" : "This attack does 20 more damage times the amount of Water Energy attached to your Pokemon.",
			"damage" : "10+",
			"convertedEnergyCost" : 2
		},
		{
			"cost" : [
				"Water",
				"Water",
				"Water",
				"Colorless"
			],
			"name" : "Roaring Seas",
			"text" : "Discard an Energy from your opponent's Active Pokemon.",
			"damage" : "120",
			"convertedEnergyCost" : 4
		},
		{
			"cost" : [
				"Colorless",
				"Colorless"
			],
			"name" : "Grand Echo-GX",
			"text" : "Heal all damage from all of your Pokemon. (You can't use more than 1 GX attack in a game.)",
			"damage" : "",
			"convertedEnergyCost" : 2
		}
	],
	"weaknesses" : [
		{
			"type" : "Grass",
			"value" : "×2"
		}
	]
}

➡️ The query above matches documents where atleast one of the array elements contains exactly 'Colorless' followed by 'Colorless', in that order. Note that arrays that contain 'Colorless', 'Colorless' and any other attacks.cost like 'Fire' or 'Water' are not returned because they are not an exact match of the filter criteria.

Exercise 11 💻

any element in the array

A more common search criteria is filtering out a single element in the array, irrespective of its array position. Note that 'Colorless' is matched irrespective of its position in the attacks.cost array. This is done by removing the [] brackets from the filter.

query:

db.cards.find({"hp":"250", "subtype": "GX", "attacks.cost": "Colorless"}).pretty()

result: (Only a part of the output has been shown.)

{
	"_id" : ObjectId("5c20177bf2e24cfe71962622"),
	"id" : "sm4-34",
	"name" : "Alolan Golem-GX",
	"nationalPokedexNumber" : 76,
	"imageUrl" : "https://images.pokemontcg.io/sm4/34.png",
	"imageUrlHiRes" : "https://images.pokemontcg.io/sm4/34_hires.png",
	"types" : [
		"Lightning"
	],
	"supertype" : "Pokemon",
	"subtype" : "GX",
	"evolvesFrom" : "Alolan Graveler",
	"hp" : "250",
	"retreatCost" : [
		"Colorless",
		"Colorless",
		"Colorless",
		"Colorless"
	],
	"convertedRetreatCost" : 4,
	"number" : "34",
	"artist" : "5ban Graphics",
	"rarity" : "Rare Holo GX",
	"series" : "Sun & Moon",
	"set" : "Crimson Invasion",
	"setCode" : "sm4",
	"text" : [
		"When your Pokemon-GX is Knocked Out, your opponent takes 2 Prize cards."
	],
	"attacks" : [
		{
			"cost" : [
				"Lightning",
				"Colorless",
				"Colorless"
			],
			"name" : "Hammer In",
			"text" : "",
			"damage" : "80",
			"convertedEnergyCost" : 3
		},
		{
			"cost" : [
				"Lightning",
				"Lightning",
				"Colorless",
				"Colorless"
			],
			"name" : "Super Electromagnetic Tackle",
			"text" : "This Pokemon does 50 damage to itself.",
			"damage" : "200",
			"convertedEnergyCost" : 4
		},
		{
			"cost" : [
				"Lightning",
				"Lightning",
				"Colorless",
				"Colorless"
			],
			"name" : "Heavy Rock-GX",
			"text" : "Your opponent can't play any cards from their hand during their next turn. (You can't use more than 1 GX attack in a game.)",
			"damage" : "100",
			"convertedEnergyCost" : 4
		}
	],
	"resistances" : [
		{
			"type" : "Metal",
			"value" : "-20"
		}
	],
	"weaknesses" : [
		{
			"type" : "Fighting",
			"value" : "×2"
		}
	]
}

➡️ This method only works if the value is not an object. We will cover how to access objects in an array in a later exercise.

Exercise 12 💻

array position (for eg: arrays whose first element match a particular criteria)

The types field is an array that indicates the type of the Pokemon. Some Pokemon are dual typed meaning they exhibit properties of 2 types of Pokemon. For example, I know that there are Pokemon which are both 'Fighting' as well as 'Metal' type.

But what if I want to know what other types are paired with 'Metal' type? In the query below, types.1: "Metal" indicates that we're looking for Pokemon cards where the 2nd element of the types array is 'Metal.'

💡 Don't forget that arrays use 0-indexing here!

query:

db.cards.find({"types.1": "Metal"}).pretty()

result: (Only a part of the output has been shown.)

{
	"_id" : ObjectId("5c20177bf2e24cfe719619e6"),
	"id" : "ex11-13",
	"name" : "Rayquaza δ",
	"nationalPokedexNumber" : 384,
	"imageUrl" : "https://images.pokemontcg.io/ex11/13.png",
	"imageUrlHiRes" : "https://images.pokemontcg.io/ex11/13_hires.png",
	"types" : [
		"Lightning",
		"Metal"
	],
	"supertype" : "Pokemon",
	"subtype" : "Basic",
	"ability" : {
		"name" : "Delta Guard",
		"text" : "As long as Rayquaza has any Holon Energy cards attached to it, ignore the effect of Rayquaza's Lightning Storm attack.",
		"type" : "Poké-Body"
	},
	"hp" : "90",
	"retreatCost" : [
		"Colorless",
		"Colorless",
		"Colorless"
	],
	"convertedRetreatCost" : 3,
	"number" : "13",
	"artist" : "Ryo Ueda",
	"rarity" : "Rare Holo",
	"series" : "EX",
	"set" : "Delta Species",
	"setCode" : "ex11",
	"text" : [
		"This Pokemon is both Lightning Metal type."
	],
	"attacks" : [
		{
			"cost" : [
				"Lightning"
			],
			"name" : "Power Blow",
			"text" : "Does 10 damage times the amount of Energy attached to Rayquaza.",
			"damage" : "10×",
			"convertedEnergyCost" : 1
		},
		{
			"cost" : [
				"Lightning",
				"Metal",
				"Colorless",
				"Colorless"
			],
			"name" : "Lightning Storm",
			"text" : "Put 7 damage counters on Rayquaza.",
			"damage" : "",
			"convertedEnergyCost" : 4
		}
	],
	"resistances" : [
		{
			"type" : "Water",
			"value" : "-30"
		},
		{
			"type" : "Fighting",
			"value" : "-30"
		}
	],
	"weaknesses" : [
		{
			"type" : "Colorless",
			"value" : "×2"
		}
	]
}

Projections

By default, MongoDB returns all fields for all matching documents as seen in all the results above. Projections reduce network overhead and processing requirements by limiting the fields that are returned in the results documents. Projections are passed as the second argument to the find() method.

Use <field name>: 1 to include that field in the results document and/or use <field name>: 0 to exclude that field. Note that the values 1 and 0 stand for inclusion and exclusion in the resulting document respectively.

Exercise 13 💻

We've written all these cool queries to try and pin point some amazing Pokemon cards so let's reduce the clutter and start by familiarizing ourselves with their names!

query:

db.cards.find(
    {"hp":"250", "subtype": "GX", "attacks.cost": "Colorless"}, 
    {"name":1})

result: (Only a part of the output has been shown.)

{ "_id" : ObjectId("5c20177bf2e24cfe71961322"), "name" : "Metagross-GX" }
{ "_id" : ObjectId("5c20177bf2e24cfe71961577"), "name" : "Primarina-GX" }
{ "_id" : ObjectId("5c20177bf2e24cfe71961681"), "name" : "Solgaleo-GX" }

In the output above, the query returns the name field as expected but the _id field gets returned by default too.

Exercise 14 💻

In order to exclude the _id field, we have to explicitly exclude it in our query.

query:

db.cards.find(
    {"hp":"250", "subtype": "GX", "attacks.cost": "Colorless"}, 
    {"name":1, "_id": 0})

result: (Only a part of the output has been shown.)

{ "name" : "Metagross-GX" }
{ "name" : "Primarina-GX" }
{ "name" : "Solgaleo-GX" }

Update Operations

The MongoDB query language supports 3 update operations:

updateOne()
updateMany()
replaceOne() - Read more 📖 about this operator.

Exercise 15 💻

Switch over to the movieDetails collections and et's turn our attention towards movies made in India ! I bet some of you have either heard of or watched the 🎥 "Taare Zameen Par" but unfortunately this collection hasn't got the name right!

Spend 5 minutes ⏰ to find out what the movie title is in our collection! Feel free to use the internet to look up identifying information like the release year or the actor/director/writer names to use in your query filter.
Once you have the name, let's update it to reflect the correct name "Taare Zameen Par".

Here's how to perform the update operation:

db.movieDetails.updateOne( {<your uniquely identifying filter as key: value pair>}, {"$set": {"title": "Taare Zameen Par"}} )

Exercise 16 💻

MongoDB offers multiple operators that can be used in its update operations. In the exercise above, we looked at the $set operator.

Name	Description
`$set`	Sets the value of a field in a document
`$unset`	Removes the specified field from a document
`$currentDate`	Sets the value of a field to current date, either as a Date or a Timestamp
`$inc`	Increments the value of a field by a specified amount
`$mul`	Multiplies the value of the field by the specified amount
`$min`	Only updates the field if the specified value is less than the existing field value.
`$max`	Only updates the field if the specified value is greater than the existing field value.
`$setOnInsert`	Sets the value of a field if an update results in an insert of a document. Has no effect on update operations that modify existing documents.
`$rename`	Renames a field

Take 10 minutes ⏰ to go through this list and write an interesting $updateMany() query against the employee_info collection we created earlier.

➡️ Note that updateMany() will make the same modification to all the documents that match the given filter.

Delete Operations

The MongoDB query language supports 2 delete operations:

deleteOne()
deleteMany()

Exercise 17 💻

In our movieDetails collection, there is only 1 movie from the year 2018 with a title "QQ Speed". To perform the exercise, delete this record.

query:

db.movieDetails.deleteOne({"title": "QQ Speed"})

Alternatively, you could use:

db.movieDetails.deleteOne({"year": 2018})

since this filter would also uniquely identify the movie "QQ Speed", considering this collection has only 1 movie from that year.

result:

{ "acknowledged" : true, "deletedCount" : 1 }

The result confirms that the deleteOne() operation was successful, at the same time telling us the number of documents that were deleted.

Exercise 18 💻

Switch back to the employee_info collection and delete one of the managers.

⚠️ In situations like these, when the filter criteria matches more than 1 document, make note that the first document to be returned is the first document to be deleted. This is an unintended consequence of such an operation so tread with caution.

On the other hand, how about we perform a deleteMany() operation against all the managers. No more managers at work! 💃

Group Activities

During this time the class should split into 5️⃣ groups to complete each section.

Activity: ⏰ 15 minutes

What is one topic that interests you most as a group?! Is it technology, climate, politics, cars, TV shows, fashion, history, outer space...? Pick a topic and write your own collection!!!

Here are a few tips to get you started:

Figure out your document structure
Come up with atleast 3 documents to insert into the collection
Show off your creativity and skills 😎 by using key:value pairs containing arrays and/or objects.

Presentation: ⏰ 25 minutes

Each group will prepare a small, 5 minute, 2-3 slide presentation about the dataset.

Present your results from the Group Activity and answer any questions your classmates may have.

Provide feedback

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01_basic-mongo-queries.md

01_basic-mongo-queries.md

CRUD Operations

Create Operations

Read Operations

Counting records

Filtering on a single field

Filtering on multiple fields

Using the "find()" method

Filtering embedded documents

Filtering array values

Projections

Update Operations

Delete Operations

Group Activities

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CRUD Operations

Create Operations

Read Operations

Counting records

Filtering on a single field

Filtering on multiple fields

Using the "find()" method

Filtering embedded documents

Filtering array values

Projections

Update Operations

Delete Operations

Group Activities