Pagination & Field Selection ↗
noOriginal Documentation
Documentation Index#
Fetch the complete documentation index at: https://docs.trychroma.com/llms.txt Use this file to discover all available pages before exploring further.
Control how many results to return and which fields to include in your search results.
export const Callout = ({title, children}) =>
{title && <p className="block mb-2"><strong>{title}</strong></p>}
{children}
;
Pagination with Limit#
Use limit() to control how many results to return and offset to skip results for pagination.
from chromadb import Search
# Limit results
search = Search().limit(10) # Return top 10 results
# Pagination with offset
search = Search().limit(10, offset=20) # Skip first 20, return next 10
# No limit - returns all matching results
search = Search() # Be careful with large collections!import { Search } from 'chromadb';
// Limit results
const search1 = new Search().limit(10); // Return top 10 results
// Pagination with offset
const search2 = new Search().limit(10, 20); // Skip first 20, return next 10
// No limit - returns all matching results
const search3 = new Search(); // Be careful with large collections!
use chroma::types::SearchPayload;
let search = SearchPayload::default().limit(Some(10), 0);
let search = SearchPayload::default().limit(Some(10), 20);
let search = SearchPayload::default();Limit Parameters#
| Parameter | Type | Default | Description |
|---|---|---|---|
limit | int or None | None | Maximum results to return (None = no limit) |
offset | int | 0 | Number of results to skip (for pagination) |
For Chroma Cloud users: The actual number of results returned will be capped by your quota limits, regardless of the limit value specified. This applies even when no limit is set.
Pagination Patterns#
# Page through results (0-indexed)
page_size = 10
# Page 0: Results 1-10
page_0 = Search().limit(page_size, offset=0)
# Page 1: Results 11-20
page_1 = Search().limit(page_size, offset=10)
# Page 2: Results 21-30
page_2 = Search().limit(page_size, offset=20)
# General formula
def get_page(page_number, page_size=10):
return Search().limit(page_size, offset=page_number * page_size)// Page through results (0-indexed)
const pageSize = 10;
// Page 0: Results 1-10
const page0 = new Search().limit(pageSize, 0);
// Page 1: Results 11-20
const page1 = new Search().limit(pageSize, 10);
// Page 2: Results 21-30
const page2 = new Search().limit(pageSize, 20);
// General formula
function getPage(pageNumber: number, pageSize = 10) {
return new Search().limit(pageSize, pageNumber * pageSize);
}use chroma::types::SearchPayload;
let page_size = 10;
// Page 0: Results 1-10
let page_0 = SearchPayload::default().limit(Some(page_size), 0);
// Page 1: Results 11-20
let page_1 = SearchPayload::default().limit(Some(page_size), 10);
// Page 2: Results 21-30
let page_2 = SearchPayload::default().limit(Some(page_size), 20);
// General Formula
fn get_page(page_number: usize, page_size: usize) -> SearchPayload {
SearchPayload::default().limit(Some(page_size), page_number * page_size)
}Pagination uses 0-based indexing. The first page is page 0, not page 1.
Field Selection with Select#
Control which fields are returned in your results to optimize data transfer and processing.
from chromadb import Search, K
# Default - returns IDs only
search = Search()
# Select specific fields
search = Search().select(K.DOCUMENT, K.SCORE)
# Select metadata fields
search = Search().select("title", "author", "date")
# Mix predefined and metadata fields
search = Search().select(K.DOCUMENT, K.SCORE, "title", "author")
# Select all available fields
search = Search().select_all()
# Returns: IDs, documents, embeddings, metadata, scoresimport { Search, K } from 'chromadb';
// Default - returns IDs only
const search1 = new Search();
// Select specific fields
const search2 = new Search().select(K.DOCUMENT, K.SCORE);
// Select metadata fields
const search3 = new Search().select("title", "author", "date");
// Mix predefined and metadata fields
const search4 = new Search().select(K.DOCUMENT, K.SCORE, "title", "author");
// Select all available fields
const search5 = new Search().selectAll();
// Returns: IDs, documents, embeddings, metadata, scores
// Default - returns IDs only
use chroma::types::{Key, SearchPayload};
let search = SearchPayload::default(); // IDs only
// Select specific fields
let search = SearchPayload::default().select([Key::Document, Key::Score]);
// Select metadata fields
let search = SearchPayload::default().select([Key::field("title"), Key::field("author")]);
// Mix predefined and metadata fields
let search = SearchPayload::default().select([
Key::Document,
Key::Score,
Key::field("title"),
Key::field("author"),
]);Selectable Fields#
| Field | Internal Key | Usage | Description |
|---|---|---|---|
| IDs | #id | Always included | Document IDs are always returned |
K.DOCUMENT | #document | .select(K.DOCUMENT) | Full document text |
K.EMBEDDING | #embedding | .select(K.EMBEDDING) | Vector embeddings |
K.METADATA | #metadata | .select(K.METADATA) | All metadata fields as a dict |
K.SCORE | #score | .select(K.SCORE) | Search scores (when ranking is used) |
"field_name" | (user-defined) | .select("title", "author") | Specific metadata fields |
Field constants: K.* constants (e.g., K.DOCUMENT, K.EMBEDDING, K.ID) correspond to internal keys with # prefix (e.g., #document, #embedding, #id). Use the K.* constants in queries. Internal keys like #document and #embedding are used in schema configuration, while #metadata and #score are query-only fields not used in schema.
When selecting specific metadata fields (e.g., “title”), they appear directly in the metadata dict. Using K.METADATA returns ALL metadata fields at once.
Performance Considerations#
Selecting fewer fields improves performance by reducing data transfer:
Minimal: IDs only (default) - fastest queries
Moderate: Add scores and specific metadata fields
Heavy: Including documents and embeddings - larger payloads
Maximum:
select_all()- returns everything# Fast - minimal data search = Search().limit(100) # IDs only # Moderate - just what you need search = Search().limit(100).select(K.SCORE, "title", "date") # Slower - large fields search = Search().limit(100).select(K.DOCUMENT, K.EMBEDDING) # Slowest - everything search = Search().limit(100).select_all()// Fast - minimal data const search1 = new Search().limit(100); // IDs only // Moderate - just what you need const search2 = new Search().limit(100).select(K.SCORE, "title", "date"); // Slower - large fields const search3 = new Search().limit(100).select(K.DOCUMENT, K.EMBEDDING); // Slowest - everything const search4 = new Search().limit(100).selectAll();
Edge Cases#
No Limit Specified#
Without a limit, the search attempts to return all matching results, but will be capped by quota limits in Chroma Cloud.
# Attempts to return ALL matching documents
search = Search().where(K("status") == "active") # No limit()
# Chroma Cloud: Results capped by quota// Attempts to return ALL matching documents
const search = new Search().where(K("status").eq("active")); // No limit()
// Chroma Cloud: Results capped by quota
Empty Results#
When no documents match, results will have empty lists/arrays.
Non-existent Fields#
Selecting non-existent metadata fields simply omits them from the results - they won’t appear in the metadata dict.
# If "non_existent_field" doesn't exist
search = Search().select("title", "non_existent_field")
# Result metadata will only contain "title" if it exists
# "non_existent_field" will not appear in the metadata dict at all// If "non_existent_field" doesn't exist
const search = new Search().select("title", "non_existent_field");
// Result metadata will only contain "title" if it exists
// "non_existent_field" will not appear in the metadata object at all
Complete Example#
Here’s a practical example combining pagination with field selection:
from chromadb import Search, K, Knn
# Paginated search with field selection
def search_with_pagination(collection, query_text, page_size=20):
current_page = 0
while True:
search = (Search()
.where(K("status") == "published")
.rank(Knn(query=query_text))
.limit(page_size, offset=current_page * page_size)
.select(K.DOCUMENT, K.SCORE, "title", "author", "date")
)
results = collection.search(search)
rows = results.rows()[0] # Get first (and only) search results
if not rows: # No more results
break
print(f"\n--- Page {current_page + 1} ---")
for i, row in enumerate(rows, 1):
print(f"{i}. {row['metadata']['title']} by {row['metadata']['author']}")
print(f" Score: {row['score']:.3f}, Date: {row['metadata']['date']}")
print(f" Preview: {row['document'][:100]}...")
# Check if we want to continue
user_input = input("\nPress Enter for next page, or 'q' to quit: ")
if user_input.lower() == 'q':
break
current_page += 1import { Search, K, Knn, type Collection } from 'chromadb';
import * as readline from 'readline';
// Paginated search with field selection
async function searchWithPagination(
collection: Collection,
queryText: string,
pageSize = 20
) {
let currentPage = 0;
const rl = readline.createInterface({
input: process.stdin,
output: process.stdout
});
while (true) {
const search = new Search()
.where(K("status").eq("published"))
.rank(Knn({ query: queryText }))
.limit(pageSize, currentPage * pageSize)
.select(K.DOCUMENT, K.SCORE, "title", "author", "date");
const results = await collection.search(search);
const rows = results.rows()[0]; // Get first (and only) search results
if (!rows || rows.length === 0) { // No more results
break;
}
console.log(`\n--- Page ${currentPage + 1} ---`);
for (const [i, row] of rows.entries()) {
console.log(`${i+1}. ${row.metadata?.title} by ${row.metadata?.author}`);
console.log(` Score: ${row.score?.toFixed(3)}, Date: ${row.metadata?.date}`);
console.log(` Preview: ${row.document?.substring(0, 100)}...`);
}
// Check if we want to continue
const userInput = await new Promise<string>(resolve => {
rl.question("\nPress Enter for next page, or 'q' to quit: ", resolve);
});
if (userInput.toLowerCase() === 'q') {
break;
}
currentPage += 1;
}
rl.close();
}Tips and Best Practices#
- Select only what you need - Reduces network transfer and memory usage
- Use appropriate page sizes - 10-50 for UI, 100-500 for batch processing
- Consider bandwidth - Avoid selecting embeddings unless necessary
- IDs are always included - No need to explicitly select them
- Use
select_all()sparingly - Only when you truly need all fields
Next Steps#
- Learn about Group By & Aggregation to diversify search results by category
- Learn about batch operations for running multiple searches
- See practical examples of pagination in production
- Explore search basics for building complete queries