Meta Query¶
Reference for the MetaQuery page of Preferences > Settings...: the MetaQuery agent that runs SQL against the MetaMiner Database (MMDB) for the MetaMiner Client (MMC), and the MetaQuery web console.
With MetaQuery, users query the collected Power BI metadata (schema pbi) with SQL.
Image of the Settings dialog, MetaQuery page, with Memory Settings, Queries, Timeout and Web console sections
../../images/admin/settings-metaquery.png
Memory Settings¶
| Field | Default | What it does | Config key |
|---|---|---|---|
| Memory allocation for MetaQuery agent: | 2 GB (or less on small machines) | Maximum memory (GB) of the MetaQuery agent process | metaquery.xmx |
| Limit max memory to quarter of physical memory | On | Caps the allocation field at a quarter of physical memory | limit.metaquery.memory.to.quarter |
Queries¶
| Field | Default | Range | What it does | Config key |
|---|---|---|---|---|
| Worker Threads: | 3 | 1 - 5 | Queries executed in parallel | query.service.agent.threads |
| Result Set Fetch Size: | 10000 | 100 - 100000 | Rows the database driver fetches per round trip | query.service.agent.result.set.fetch.size |
| Result Set Threshold: | 5 | 5 - 50 | Result sets up to this size (MB) are sent to the client in one piece | query.service.agent.small.result.set.threshold.mb |
| Allow Write Commands | Off | - | Allows statements such as INSERT and DELETE | query.service.agent.allow.write.commands |
| Convert Unknown Types | Off | - | Converts database-specific column types (for example intervals) to text | query.service.agent.convert.result.set.unknown.types.to.string |
Keep write commands off
With Allow Write Commands on, MetaQuery users can change or delete MMDB data. Leave it off.
Timeout¶
| Field | Default | Range | What it does | Config key |
|---|---|---|---|---|
| MetaQuery timeout period (mins): | 10 | 5 - 20 | Cancels a MetaQuery that runs longer than this | metaquery.timeout |
Long timeouts let poorly tuned queries slow down the whole MMDB, including collection.
Web console¶
| Field | Default | What it does | Config key |
|---|---|---|---|
| Enable the web console (/web/metaquery) | Off | Turns on MetaQuery in the browser. Users sign in with MetaMiner accounts that have the Meta Query permission on an environment. | web.metaquery.enabled |
| Allow anonymous use (lower limits, nothing saved) | Off | Lets anyone who can reach the server run read-only SQL without signing in | allow.anonymous.web.metaquery |
| Allow sign-in over plain HTTP (password sent unencrypted) | Off | Off: a browser on another computer can sign in only over HTTPS. On: also over plain HTTP. | web.metaquery.http.signin |
Per-tier limits (Timeout (s) and Row cap):
| Tier | Timeout default | Row cap default | Config keys |
|---|---|---|---|
| Users: | 600 s | 1,000,000 | web.metaquery.timeout.sec.user, web.metaquery.rowcap.user |
| MMDB administrators: | 1800 s | 5,000,000 | web.metaquery.timeout.sec.admin, web.metaquery.rowcap.admin |
| Anonymous: | 120 s | 100,000 | web.metaquery.timeout.sec.anon, web.metaquery.rowcap.anon |
Timeouts range from 10 to 86400 seconds; row caps from 1,000 to 50,000,000. Web console settings apply without a server restart.
Anonymous access and plain HTTP
Leave anonymous use and plain-HTTP sign-in off unless the server is on a trusted network. Enable MetaMiner Server SSL for remote browser access.