Realtime Capabilities

LinkedQL brings reactivity to the database layer, letting queries directly drive application state.

On any given database, LinkedQL lets you have live queries as a first-class capability, and directly supports table-level subscriptions.

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Meet Live Queries

const result = await db.query(`
  SELECT
    p.title,
    p.category,
    author ~> { name, email } AS author
  FROM posts AS p
  WHERE p.published = true
  ORDER BY p.created_at DESC
`, { live: true });

No need for a separate subscription layer (like a GraphQL server) in front of your database. Your query is the subscription.

result is the same shape as a regular query result but self-updating as the database changes over time.

Updates are pushed from the database to the client—no polling, no manual subscriptions:

• automatically stays current over time
• directly powers reactivity across the app

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Meet Changefeeds (Direct Table-Level Subscriptions)

const unsubscribe = await db.wal.subscribe({ public: ['users'] }, (commit) => {
  console.log(commit);
});

Sometimes you need changes at the table or commit level, not a query result.

db.wal.subscribe() exposes commit-level events from the database’s change stream::

• PostgreSQL's Write Ahead Log (WAL)
• MySQL/MariaDB's Binary Log (Binlog)
• FlashQL's Write Ahead Log (WAL)

It's especially useful for replication flows, synchronization logic, and downstream processors.

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The Broader Idea

In a traditional stack, reactivity is assembled from multiple layers:

• the database
• a subscription server and/or a sync engine
• app-level invalidation logic
• client caches or replicas

LinkedQL pushes the behaviour itself into where the data already lives: the database, collapsing that stack back into the database layer.

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Documentation

Capability	What It Adds	Docs
Live Queries	Queries that work in live mode and return real-time results	Live Queries
Changefeeds	Direct table-level commit stream	JSON Literals