| 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
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.
