sessions.md

title	Sessions & changesets
description	Record database changes into changesets/patchsets, apply them to a replica, invert and concat — the offline-sync primitive.
sidebar	order 13

Sessions & changesets (SESSION extension)

The SESSION extension records the changes made on a database into a changeset (or patchset), which you can serialize, ship, and replay onto another database — the foundation for offline sync, audit logs, and lightweight replication. SQLITE_ENABLE_SESSION is compiled into the lib; no other pure-Go SQLite driver exposes this.

sc, _ := db.Conn(ctx)
sc.Raw(func(dc any) error {
	c := dc.(*sqlite.Conn)
	sess, _ := c.CreateSession("main")
	defer sess.Close()
	sess.Attach("")            // track all tables (or a specific table name)

	// ... run INSERT/UPDATE/DELETE on c ...

	cs, _ := sess.Changeset()  // []byte; or sess.Patchset()
	// ship cs to a replica, then on the replica's conn:
	return replicaConn.ApplyChangeset(cs,
		sqlite.WithConflictHandler(myHandler),
		sqlite.WithTableFilter(myFilter))
})

API surface (on *sqlite.Conn): CreateSession → *Session (Attach / Enable / Changeset / Patchset / Diff / Close); ApplyChangeset (with WithConflictHandler / WithTableFilter), InvertChangeset (undo), ConcatChangesets (merge).

Runnable: examples/features/advanced/session/ — record on a primary, replay onto a replica, then undo via InvertChangeset.