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spacetimedb-sql

spacetimedb-sql

github.com/danmossaData & databases2164 installsUpdated 19w ago
Repository

About spacetimedb-sql

A skill covering SpacetimeDB SQL syntax and query behavior. It distinguishes subscription restrictions from ad hoc queries and data changes, with guidance on indexes and joins.

Key features

  1. 01Subscription SQL restrictions
  2. 02Ad hoc SELECT and DML forms
  3. 03Identifiers and literal syntax
  4. 04Index and join guidance

Use cases

  1. 01Writing valid table subscriptions
  2. 02Constructing SQL queries and mutations
  3. 03Reviewing indexes for subscription joins

Install

Copy the command and run it in a terminal.

$npx skills add https://github.com/danmossa/spacetimedb-skills --skill spacetimedb-sql

After installing, type/spacetimedb-sqlin Claude Code to confirm it loaded.

Bundled filesreferences/reference-sql.md

Details

From the project README

Use this skill for SQL syntax and query behavior.

Core SQL split

Subscription SQL is stricter than ad hoc query/DML SQL:

  • Subscription form is SELECT projection FROM relation [WHERE predicate].
  • Subscriptions return full rows from one table only: SELECT * or SELECT table.*.
  • Subscriptions can reference at most two tables with one join, and join columns must be indexed.
  • Subscriptions do not support INSERT, UPDATE, DELETE, column projections, arithmetic expressions, or arbitrary joins.

Ad hoc SQL via CLI/HTTP supports:

  • SELECT with column projections, COUNT(*), joins, WHERE, and LIMIT.
  • INSERT INTO table (columns...) VALUES (...).
  • DELETE FROM table [WHERE ...]; no joins.
  • UPDATE table SET column = literal [WHERE ...]; no joins.
  • Experimental SET and SHOW system-variable statements.

Query guidance

  • Table names in SQL are the exact schema table names, not generated accessor names.
  • String literals use single quotes. Identifiers are case-sensitive; quote reserved words or unusual names with double quotes.
  • Hex literals can represent identities, connection IDs, or binary values when the context type is known.
  • Index filtered columns and join columns, especially for subscriptions.
  • Place the most selective table/filter first in join-heavy ad hoc queries.

Reference map

NeedOpen
SpacetimeDB SQL referencereferences/reference-sql.md

Guidance

  • Distinguish subscription SQL from mutation/query SQL when explaining allowed forms.
  • Check table and index definitions before recommending query changes for performance.
  • Route CLI execution details to spacetimedb-cli.

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