One-shot queries
A serverless function executes one database operation per request.
Neon · Const
HTTP driver
Neon’s HTTP driver uses the neon() function from @neondatabase/serverless to issue Postgres queries through HTTP fetch requests. It is designed for serverless and edge runtimes, especially for single queries and non-interactive transactions.
How it works
The HTTP driver uses the neon() function from @neondatabase/serverless. It returns a tagged-template query function that sends each query through fetch, avoiding a persistent connection and making it suitable for serverless and edge runtimes.
Syntax
neon(connectionString)Parameters
| Name | Type | Description |
|---|---|---|
connectionString | string | Neon Postgres connection string, normally supplied from an environment variable. |
Returns
A tagged-template query function for executing SQL over HTTP.
Key points
- Each query is transmitted through an HTTP fetch request rather than a persistent database socket.
- The HTTP entry point is the
neonfunction provided by the serverless driver. - HTTP is optimized for low-latency execution of individual queries.
Common mistakes
- Use the returned function as a tagged template; do not call it like a conventional query method or construct SQL by concatenating user input.
- HTTP queries have a 64 MB limit for both the request and the response.
Example: Run a query over HTTP
import { neon } from '@neondatabase/serverless';
const sql = neon(process.env.DATABASE_URL!);
const users = await sql`SELECT id, name FROM users WHERE active = ${true}`;
console.log(users);Creates the HTTP query function and executes a parameterized SQL query.
When to use it
Edge-runtime database access
An edge function runs SQL where a persistent TCP connection is unsuitable.
Non-interactive transactions
Several statements must run together without interactive session behavior.
Interview questions
QHow does Neon’s HTTP driver execute queries?
The HTTP interface is the neon() function from @neondatabase/serverless. It sends each query as an HTTP fetch request, which avoids maintaining a database connection and is optimized for serverless and edge runtimes.
Follow-up: When should WebSockets be preferred? Use the driver's Pool or Client when the application needs session state or interactive transactions.
QWhy is the HTTP driver's tagged-template interface useful?
neon() returns a query function designed to be used as a tagged template. Interpolated values are handled as query parameters, helping protect against SQL injection.
Follow-up: What is the corresponding limitation? The returned function is intended for tagged-template use rather than ordinary string-built SQL calls.
QWhen is the HTTP driver a good fit?
HTTP is the default choice for single queries and non-interactive transactions. Multiple statements can also be grouped with the driver's transaction function when they do not require interactive session behavior.
Follow-up: What constraint applies to HTTP payloads? Both the request and response are limited to 64 MB.
Related
@neondatabase/serverlessneon()WebSocketsPoolClienttransaction()