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.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains Caching policy in context, with comparison tables and the common traps.
Terms in this definition
- KQL database
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.
- Event
Table in Log Analytics where entries from Windows event logs are kept.
- LSDOU
The sequence in which Group Policy is processed: the local policy first, followed by site, domain and organisational unit policies. The nearest, last-processed setting takes effect unless Enforced or Block Inheritance alters that.
- SSD
Flash-based solid-state storage that underpins Premium disks and storage.
- Hot
The online blob access tier where storing data costs the most but accessing it costs the least.
- OVER
Gives a T-SQL window function its window: PARTITION BY, ORDER BY and, if wanted, a ROWS or RANGE frame. Rankings and running totals can then be worked out while every row is kept.
- MANAGE
A Unity Catalog privilege allowing a principal to grant and revoke access on an object, hand over its ownership and drop it, all without being the owner. It gives no data access by itself and is not part of
ALL PRIVILEGES.
Related terms
- 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.