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Projection & Sorting

mongo-projectionmongodbprojectionsortpagination

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Full lesson · 8 learning steps Open any exercise for focused practice

Step 1 of 8 · intro card

Learn Projection & Sorting

Query Operators

Shape results after filtering: a projection picks which fields to return, .sort orders them, and .skip + .limit page through the set.

A projection is the second argument to find(): set fields to 1 to include or 0 to exclude; _id is returned unless you set it to 0.

.sort orders the cursor by one or more fields, with 1 ascending and -1 descending.

.skip(N).limit(M) implements pagination — skip past earlier pages and return only M documents.

Projection 1 includes a field, 0 excludes it.

.sort({ field: -1 }) sorts descending, 1 ascending.

.skip + .limit page through ordered results.

db.users.find({}, { name: 1, _id: 0 })
db.users.find({}).sort({ age: -1 })
db.users.find({}).sort({ age: -1 }).limit(10)
db.users.find({}).sort({ age: -1 }).skip(20).limit(10)

Read the implementation

Connect each part of the code to the concept before you type.

1. Pick fields

The second find() argument is a projection: 1 includes a field, 0 excludes it; _id is included unless you set it to 0.

{ name: 1, _id: 0 }

2. Order results

.sort orders documents: -1 is descending, 1 is ascending.

.sort({ age: -1 })

3. Cap the count

.limit caps how many documents the cursor returns.

.limit(10)

4. Skip ahead

.skip jumps past the first N documents, paired with limit for paging.

.skip(20)

A complete learning loop

Understand

Read the concept map and follow the code breakdown.

Reconstruct

Type the implementation, repair mistakes and work through every recall exercise.

Verify

Use the final check without hints; revisit weak concepts in short practice sessions.