MMDB Overview¶

The MetaMiner Database (MMDB) is the PostgreSQL database where the MetaMiner Server (MMS) stores all collected Power BI metadata, activity, capacity metrics and its own operational data.

How it works¶

The MMDB is one PostgreSQL database, named metaminer by default, with one schema per area.

Schema	Content
`pbi`	Power BI, Fabric and Microsoft Entra ID data: workspaces, items, semantic models, lineage, users, activity events, refreshes, capacity metrics, backup jobs
`silver`	Pre-computed daily and hourly rollups that feed the Power BI usage dashboards
`mms`	MetaMiner operational data: dashboard job runs, saved MetaQuery queries, pull history
`metrics`	Server metrics
`public`	SAP BusinessObjects metadata and shared tables
`tableau`, `snowflake`	Other platforms; created only when licensed

MMS creates and updates the schemas itself. Every time it starts it applies any pending database updates shipped with the release, so after an upgrade the first start can take longer.

PostgreSQL 16 or newer for Power BI

The Power BI schema needs PostgreSQL 16 or newer. On an older MMDB, MMS does not create or update the pbi schema and collects nothing for Power BI, and MMA refuses to enable Power BI environments. The embedded database is PostgreSQL 16.

flowchart LR
  MS[Microsoft APIs] -->|collectors| MMS[MetaMiner Server]
  MMS -->|read / write| MMDB[(MMDB metaminer)]
  MMC[MetaMiner Client] -->|via MMS| MMS
  WEB[Usage dashboards] -->|read| MMDB
  MQ[MetaQuery web console] -->|read-only roles| MMDB

Database types¶

Active DB Type	Use it when	Page
Postgres (embedded) (default)	PostgreSQL installed and managed by MetaMiner on the MetaMiner Server machine	Embedded PostgreSQL
Postgres	Your DBA runs PostgreSQL 16 or newer on another server	External PostgreSQL

Database roles¶

Role	Used by	Access
`mmuser`	MMS	Owner of the MetaMiner database (embedded default)
`readonly`	Read-only consumers	Read-only on the MetaMiner schemas
`mq_reader`, `mq_reader_all`	MetaQuery web console	Read-only, with statement timeouts and connection limits

MMS creates and maintains readonly and the MetaQuery roles at each start.

Configure MMDB dialog¶

Click Configure MMDB in the MMA main window.

Element	Purpose
Active DB Type:	Postgres (embedded) or Postgres
DBMS Host:, Port:, DB Name:, Username:, Password:	Connection to the MMDB
SSL	Encrypts the connection (external PostgreSQL)
Superuser password:	Password of the PostgreSQL `postgres` superuser (embedded only)
Embedded database panel	Start, stop, restart or create the embedded database; see Embedded PostgreSQL
DB Console	Opens a browser SQL console; see Database Console
MMDB Stability Advisor	Read-only check of memory-related database settings
Re-check	Probes the database again with the connection shown
Validate and Close	Tests the connection, saves and closes

Image of the Configure MMDB dialog with Postgres (embedded) selected, the Embedded database panel and the MMDB Stability Advisor

../../images/admin/configure-mmdb.png

MMDB Stability Advisor¶

The advisor reads PostgreSQL memory settings, database size and the machine's memory, and shows each setting with Current, Recommended and Status (OK, Attention, Risky, Unknown). It only reads; it never changes the database. Apply recommendations yourself or with your DBA.