Schema versioning strategies in MongoDB - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to add a version field to a MongoDB document.

MongoDB

db.collection.insertOne({ name: "Alice", age: 30, version: [1] })

Drag options to blanks, or click blank then click option'

A1

B"v1"

Ctrue

Dnull

Attempts:

3 left

💡 Hint

Common Mistakes

Using a string instead of a number for version.

Omitting the version field entirely.

The version field is typically a number to track schema versions. Here, 1 is used.

2fill in blank

medium

Complete the code to update the schema version of all documents to 2.

MongoDB

db.collection.updateMany({}, { $set: { version: [1] } })

Drag options to blanks, or click blank then click option'

A2

B"2"

Ctrue

Dnull

Attempts:

3 left

💡 Hint

Common Mistakes

Using a string "2" instead of number 2.

Using null or true instead of a version number.

Schema versions are numeric. Here, we set version to 2 as a number.

3fill in blank

hard

Fix the error in the query to find documents with version 1.

MongoDB

db.collection.find({ version: [1] })

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A"1"

B1

Ctrue

Dnull

Attempts:

3 left

💡 Hint

Common Mistakes

Using a string "1" which does not match the numeric field.

Using true or null which are incorrect types.

The version field is stored as a number, so the query must use number 1, not string "1".

4fill in blank

hard

Fill both blanks to add a new field only to documents with version less than 2.

MongoDB

db.collection.updateMany({ version: { [1]: 2 } }, { $set: { [2]: "legacy" } })

Drag options to blanks, or click blank then click option'

A$lt

B$gt

Cstatus

Dversion

Attempts:

3 left

💡 Hint

Common Mistakes

Using $gt instead of $lt for filtering.

Setting the field name as 'version' which overwrites existing data.

Use $lt to find documents with version less than 2, and add a new field 'status' with value 'legacy'.

5fill in blank

hard

Fill all three blanks to rename the field 'oldField' to 'newField' in documents with version 1.

MongoDB

db.collection.updateMany({ version: [1] }, { $rename: { [2]: [3] } })

Drag options to blanks, or click blank then click option'

A1

B"oldField"

C"newField"

D"version"

Attempts:

3 left

💡 Hint

Common Mistakes

Using version as a string instead of number.

Not quoting field names in $rename operator.

We filter documents with version 1, then rename 'oldField' to 'newField' using $rename operator.