Implements efficient API pagination using offset, cursor, and keyset strategies for large datasets. Use when building paginated endpoints, implementing infinite scroll, or optimizing database queries for collections.
Implement scalable pagination strategies for handling large datasets efficiently.
| Strategy | Best For | Performance |
|---|---|---|
| Offset/Limit | Small datasets, simple UI | O(n) |
| Cursor | Infinite scroll, real-time | O(1) |
| Keyset | Large datasets | O(1) |
app.get('/products', async (req, res) => {
const page = parseInt(req.query.page) || 1;
const limit = Math.min(parseInt(req.query.limit) || 20, 100);
const offset = (page - 1) * limit;
const [products, total] = await Promise.all([
Product.find().skip(offset).limit(limit),
Product.countDocuments()
]);
res.json({
data: products,
pagination: {
page,
limit,
total,
totalPages: Math.ceil(total / limit)
}
});
});
app.get('/posts', async (req, res) => {
const limit = 20;
const cursor = req.query.cursor;
const query = cursor
? { _id: { $gt: Buffer.from(cursor, 'base64').toString() } }
: {};
const posts = await Post.find(query).limit(limit + 1);
const hasMore = posts.length > limit;
if (hasMore) posts.pop();
res.json({
data: posts,
nextCursor: hasMore ? Buffer.from(posts[posts.length - 1]._id).toString('base64') : null
});
});
{
"data": [...],
"pagination": {
"page": 2,
"limit": 20,
"total": 150,
"totalPages": 8
},
"links": {
"first": "/api/products?page=1",
"prev": "/api/products?page=1",
"next": "/api/products?page=3",
"last": "/api/products?page=8"
}
}