spacetimedb-views

name	spacetimedb-views
description	Use when defining SpacetimeDB views, SQL-backed projections, derived client-facing data, view arguments, or view performance. Triggers on: view, views, derived data, SQL view, view argument, projection, client query.
license	MIT

Use this skill for derived data exposed through SpacetimeDB views.

Core view patterns

Views expose read-only, derived data to clients. Use them for filtered or joined results that should be computed server side instead of duplicating rows into another table.

TypeScript view shape:

export const high_scorers = spacetimedb.anonymousView(
  { name: "high_scorers", public: true },
  t.array(players.rowType),
  (ctx) =>
    ctx.from.players
      .where((p) => p.score.gte(1000n))
      .where((p) => p.name.ne("BOT")),
);

Design rules

• Views must be public and have explicit names.
• Views are read-only. Use reducers for writes and tables for stored state.
• Use anonymousView/AnonymousViewContext when every caller sees the same result; SpacetimeDB can share one materialized result across subscribers.
• Use per-user ViewContext only when the result depends on the caller, such as "my inventory" or private messages.
• Keep the read set small. Prefer indexed lookups or the module-side query builder for filters and joins.
• Do not default to .iter() for views; load the reference for query-builder syntax, .iter() limitations, and primary-key inference details.

Reference map

Need	Open
View definitions and examples	references/functions-views.md

Guidance

• Use views when the user needs derived or filtered data rather than duplicated stored rows.
• Check the SQL reference for expression or query syntax details.
• Check table indexes before adding views that may become hot subscription paths.