cube-js/cube · error

Undefined dbType or dialectClass for '${cube}'

Error message

Undefined dbType or dialectClass for '${cube}'

What it means

The cube name exists in the factory map but maps to a falsy QueryClass (undefined). This happens when the cube's dbType is missing/unknown and no dialectClass was provided, so the factory registered a null mapping and cannot instantiate a query.

Source

Thrown at packages/cubejs-schema-compiler/src/adapter/QueryFactory.ts:13

export class QueryFactory {
  public constructor(
    private cubeToQueryClass: Record<string, any>,
  ) {
  }

  public createQuery(cube: string, compilers: any, queryOptions: any) {
    if (!(cube in this.cubeToQueryClass)) {
      throw new Error(`Undefined cube '${cube}'`);
    }
    const QueryClass = this.cubeToQueryClass[cube];
    if (!QueryClass) {
      throw new Error(`Undefined dbType or dialectClass for '${cube}'`);
    }
    return new QueryClass(compilers, queryOptions);
  }
}

View on GitHub (pinned to 7d981676b3)

Solutions

1. Set a valid dbType for the cube in your data model (one supported by ADAPTERS)
2. Pass queryOptions.dialectClass with a custom query class if using a custom dialect
3. Check driver registration / imports so the adapter for the dbType is available

Example fix

// before
cube('Events', { sql: ..., /* dbType missing or unsupported */ });
// after
cube('Events', { sql: ..., dataSource: 'default' }); // with driver/dbType registered, or pass dialectClass

if (cube in cubeToQueryClass && !cubeToQueryClass[cube]) throw new Error(`Cube '${cube}' has no resolvable dbType/dialect; set dbType or dialectClass`);

try { return factory.createQuery(cube, compilers, options); } catch (e) { if (/Undefined dbType or dialectClass/.test(e.message)) { /* prompt for dialectClass or fix dbType */ } throw e; }

When it happens

Trigger: createQuery(cube, ...) where the cube was registered with an undefined query class — typically because the cube's dataSource/dbType is not recognized by ADAPTERS and queryOptions.dialectClass was not supplied.

Common situations: Schema cube declares an unsupported or misspelled sql/dbType; custom dialect expected via dialectClass but not passed in compiler options; driver package not registered before compiling.

Related errors

• Unknown dbType: ${dbType}
• Dialect for '${queryOptions.externalDbType}' is not found
• Can't find dialect for '${dataSource}' data source: ${_dbTyp
• A user-defined contextToApiScopes function returns an incons
• A user-defined contextToApiScopes function returns a wrong s

AI-assisted analysis of cube-js/cube@7d981676b3 (2026-09-02). Data as JSON: /api/errors/fbc68ffc0f948aef. Report an issue: GitHub.