Connecting to multiple data sources

A Cube Cloud deployment always has a single default data source plus, optionally, one or more named data sources. Cubes reference whichever source they need via the data_source property.

Manage data sources from your deployment's Settings → Data Sources page.

Adding a data source

Click + Add data source, pick the driver, give the source a short name (see Source name rules), and fill in the connection form — the same form the deployment wizard uses.

Cube Cloud tests the connection before saving; on success it persists the env vars and restarts the development environment, on failure it surfaces the driver's error and saves nothing.

Editing and deleting

Use the Edit action on a row to update credentials, or the Delete action to remove a named source. The default source can be edited but not deleted — to remove it, clear the bare CUBEJS_DB_* variables from Settings → Environment Variables by hand.

Source name rules

• Letters, digits, and underscores; must start with a letter.
• default is reserved; use the Use as default button on the naming step instead.
• Flat names (analytics, warehouse) are safer than names with underscores, which can collide with the env-var parser when they end in _db, _aws, or _jdbc.

Using a data source from a cube

Reference a source from the data_source property using the name you gave it when you created it:

cubes:
  - name: orders_from_other_data_source
    # ...
    data_source: analytics

cube(`orders_from_other_data_source`, {
  // ...
  data_source: `analytics`
})

Cubes that don't set data_source use the default source — there's no need to write data_source: default explicitly, though you can if you prefer to be explicit.

For multitenancy scenarios where the data source is selected dynamically per request, see driver_factory and the multitenancy guide.

Workbooks

Sources show up immediately in Workbooks — open a Source SQL tab and they appear in the data sources sidebar without needing a cube to reference them first.

Under the hood

The UI is a friendlier surface over the deployment's environment variables — inspect or hand-edit them from Settings → Environment Variables at any time.

The default source uses bare CUBEJS_DB_* variables; each named source uses a CUBEJS_DS_<NAME>_* prefix. CUBEJS_DATASOURCES is auto-maintained whenever at least one named source exists, with default first and named entries lowercased:

CUBEJS_DATASOURCES=default,analytics
CUBEJS_DB_TYPE=postgres
CUBEJS_DB_HOST=localhost
CUBEJS_DS_ANALYTICS_DB_TYPE=postgres
CUBEJS_DS_ANALYTICS_DB_HOST=remotehost

For the full list of variables that support decoration, see the environment variables reference.