paperclipai/paperclip · error · Error

ctx.db.query cannot contain mutation or DDL keywords

Error message

ctx.db.query cannot contain mutation or DDL keywords

What it means

Keyword ban inside runtime SELECT: even statements that start with select/with are rejected if they contain insert/update/delete/alter/create/drop/truncate anywhere (e.g. inside CTEs). Defense in depth ensuring ctx.db.query can never mutate; the smuggled keyword query is at fault.

Source

Thrown at server/src/services/plugin-database.ts:262

}

export function validatePluginRuntimeQuery(
  query: string,
  namespace: string,
  coreReadTables: readonly PluginDatabaseCoreReadTable[] = [],
): void {
  const statements = splitSqlStatements(query);
  if (statements.length !== 1) {
    throw new Error("Plugin runtime SQL must contain exactly one statement");
  }
  const statement = statements[0]!;
  assertNoBannedSql(statement);
  const normalized = normaliseSql(statement);
  if (!normalized.startsWith("select ") && !normalized.startsWith("with ")) {
    throw new Error("ctx.db.query only allows SELECT statements");
  }
  if (/\b(insert|update|delete|alter|create|drop|truncate)\b/.test(normalized)) {
    throw new Error("ctx.db.query cannot contain mutation or DDL keywords");
  }

  const allowedCoreReadTables = new Set(coreReadTables);
  for (const ref of extractQualifiedRefs(statement)) {
    if (ref.schema === namespace) continue;
    if (ref.schema === "public") {
      assertAllowedPublicRead(ref, allowedCoreReadTables);
      continue;
    }
    throw new Error(`ctx.db.query cannot read schema "${ref.schema}"`);
  }
}

export function validatePluginRuntimeExecute(query: string, namespace: string): void {
  const statements = splitSqlStatements(query);
  if (statements.length !== 1) {
    throw new Error("Plugin runtime SQL must contain exactly one statement");
  }

View on GitHub (pinned to 120ae5428f)

Solutions

1. Remove mutation or DDL keywords from the ctx.db.query SQL; use SELECT only.

When it happens

Trigger: Thrown at server/src/services/plugin-database.ts:262 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of paperclipai/paperclip@120ae5428f (2026-08-18). Data as JSON: /api/errors/0fa950a659e36af1. Report an issue: GitHub.