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Manage Data with TTL (Time-to-live) | ClickHouse Docs

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TTL (time-to-live) refers to the capability of having rows or columns moved, deleted, or rolled up after a certain interval of time has passed. While the expression "time-to-live" sounds like it only applies to deleting old data, TTL has several use cases: TTL can be applied to entire tables or specific columns. The TTL clause can appear after a column definition and/or at the end of the table definition. Use the INTERVAL clause to define a length of time (which needs to be a Date or DateTime data type). For example, the following table has two columns with TTL clauses: TTL rules can be altered or deleted. See the Manipulations with Table TTL page for more details. The deleting or aggregating of expired rows is not immediate - it only occurs during table merges. If you have a table that's not actively merging (for whatever reason), there are two settings that trigger TTL events: So by default, your TTL rules will be applied to your table at least once every 4 hours. Just modify the set

Edit this page Overview of TTL ​ TTL (time-to-live) refers to the capability of having rows or columns moved, deleted, or rolled up after a certain interval of time has passed. While the expression "time-to-live" sounds like it only applies to deleting old data, TTL has several use cases: Removing old data: no surprise, you can delete rows or columns after a specified time interval Moving data between disks: after a certain amount of time, you can move data between storage volumes - useful for deploying a hot/warm/cold architecture Data rollup: rollup your older data into various useful aggreg

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