Set `status` to `"archived"` for all posts with `views` less than `100`. Return the count of archived posts.

Problem Statement

<p>Set <code>status</code> to <code>"archived"</code> for all <code>posts</code> with <code>views</code> less than <code>100</code>. Return the count of archived <code>posts</code>.</p>

Examples

Input: posts collection: +-----+---------+-------+-----------+ | _id | title | views | status | +-----+---------+-------+-----------+ | 1 | Popular | 500 | published | | 2 | Meh | 50 | published | | 3 | Old | 10 | published | | 4 | Viral | 10000 | published | +-----+---------+-------+-----------+

Output: +-------+ | count | +-------+ | 2 | +-------+

Explanation: The target document is modified according to the update operators and the updated document is returned.

Complexity

Time Complexity: -

Space Complexity: -

Hints

💡 Hint 1: Use comparison operators ($gt, $gte, $lt, $lte) to filter documents based on numeric or date ranges. 💡 Hint 2: Construct the filter condition: { fieldName: { $gt: value } } inside db.<collection>.find(...). 💡 Hint 3: Chain projection or sorting if requested, and invoke .toArray() to produce the result array.

Editorial & Approach

Problem Overview & Intuition

To solve "Conditional Update Then Verify", we query the MongoDB document store. The goal is to set `status` to `"archived"` for all posts with `views` less than `100`. return the count of archived posts. Using a targeted find query, the database engine filters and structures the BSON documents efficiently.

Step-by-Step Approach

Identify Target Collection: Access the collection through the db instance.
Construct Query / Pipeline: Build the query filter with appropriate comparison operators.
Resolve Cursor: Invoke .toArray() to transform the query cursor into the required array of documents.

Optimal Implementation (MongoDB)

function solve(db) {
  db.posts.updateMany({ views: { $lt: 100 } }, { $set: { status: "archived" } });
  return db.posts.countDocuments({ status: "archived" });
}

Complexity Analysis

Time Complexity O(N) collection scan (O(log N) if index is present on filtered fields).

Space Complexity O(K) where K is the number of returned documents in memory.

Key Considerations & Edge Cases

Empty Collections: If no documents match, the query cleanly returns an empty array [].
Missing / NULL Fields: Missing fields in documents are handled safely without throwing runtime exceptions.
Type Coercion: BSON types (ObjectId, Numbers, Strings) are compared strictly according to MongoDB specifications.

Conditional Update Then Verify

Medium

Set status to "archived" for all posts with views less than 100. Return the count of archived posts.

Example Scenarios

1Example 1

Input:

posts collection

_id	title	views	status
1	Popular	500	published
2	Meh	50	published
3	Old	10	published
4	Viral	10000	published

Output:

count
2

Explanation:

The target document is modified according to the update operators and the updated document is returned.

MongoDB Editor

Loading Editor...

Query Results (JSON)

Run your MongoDB code to see results here.