Lives within a Microsoft Fabric eventhouse and keeps tables that you query in KQL. One eventhouse may contain several of them, and each can hold many tables.
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In the Ultra Transcenders books
Each book explains KQL database in context, with comparison tables and the common traps.
Terms in this definition
- Microsoft Fabric
Analytics platform from Microsoft delivered as SaaS on top of OneLake, offering capabilities including Direct Lake and shortcuts.
- Eventhouse
Holds one or more KQL databases and is where Real-Time Intelligence in Microsoft Fabric keeps time-stamped streaming events for analysis, indexed by the moment they arrive.
- KQL
Kusto Query Language, used read-only to query Azure Data Explorer, Log Analytics and Microsoft Sentinel; log alert rules are written in it too.
Related terms
- Caching policy
Determines the period for which KQL database or table data is held on local SSD in the hot cache so that queries over it are quick. The period may not exceed retention, and you configure it from Manage > Data policies.
- Data retention policy
Automatically deletes KQL database or table data once it's older than a configured age (by default 3,650 days). You set it in Manage > Data policies, next to the caching policy, and it applies to the OneLake copy of the data too.
- Database shortcut
Read-only by design, this eventhouse KQL database references another KQL or Azure Data Explorer database and keeps in sync with it, with no ingestion of its own. You can adjust its principals, permissions and caching policy, but nothing else.
- Ingestion batching policy
A policy, set on a KQL database or on individual tables, that decides when queued ingestion closes off a batch: whichever comes first of a time, item-count or size limit (5 minutes, 500 items or 1 GB uncompressed by default). A policy on a table wins over one on its database.
- OneLake availability
When switched on for a KQL database or table (it starts disabled), an Eventhouse exposes that data in OneLake in Delta format. Other Fabric engines, Direct Lake included, can then read it without anyone copying it.
- Workspace monitoring
A preview capability that a workspace Admin can switch on, if the tenant permits, to gather metrics and logs from that workspace's items into a monitoring eventhouse. Its KQL database is read-only, holds tables such as ItemJobEventLogs and keeps data for 30 days unless changed.