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### ClickHouse release 24.8 LTS, 2024-08-20. [Presentation](https://presentations.clickhouse.com/2024-release-24.8/), [Video](https://www.youtube.com/watch?v=AeLmp2jc51k)[​](#a-id248a-clickhouse-release-248-lts-2024-08-20 "Direct link to a-id248a-clickhouse-release-248-lts-2024-08-20")

#### Backward Incompatible Change[​](#backward-incompatible-change-4 "Direct link to Backward Incompatible Change")

- `clickhouse-client` and `clickhouse-local` now default to multi-query mode (instead single-query mode). As an example, `clickhouse-client -q "SELECT 1; SELECT 2"` now works, whereas users previously had to add `--multiquery` (or `-n`). The `--multiquery/-n` switch became obsolete. INSERT queries in multi-query statements are treated specially based on their FORMAT clause: If the FORMAT is `VALUES` (the most common case), the end of the INSERT statement is represented by a trailing semicolon `;` at the end of the query. For all other FORMATs (e.g. `CSV` or `JSONEachRow`), the end of the INSERT statement is represented by two newlines `\n\n` at the end of the query. [#63898](https://github.com/ClickHouse/ClickHouse/pull/63898) ([FFish](https://github.com/wxybear)).
- In previous versions, it was possible to use an alternative syntax for `LowCardinality` data types by appending `WithDictionary` to the name of the data type. It was an initial working implementation, and it was never documented or exposed to the public. Now, it is deprecated. If you have used this syntax, you have to ALTER your tables and rename the data types to `LowCardinality`. [#66842](https://github.com/ClickHouse/ClickHouse/pull/66842) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- Fix logical errors with storage `Buffer` used with distributed destination table. It's a backward incompatible change: queries using `Buffer` with a distributed destination table may stop working if the table appears more than once in the query (e.g., in a self-join). [#67015](https://github.com/ClickHouse/ClickHouse/pull/67015) ([vdimir](https://github.com/vdimir)).
- In previous versions, calling functions for random distributions based on the Gamma function (such as Chi-Squared, Student, Fisher) with negative arguments close to zero led to a long computation or an infinite loop. In the new version, calling these functions with zero or negative arguments will produce an exception. This closes [#67297](https://github.com/ClickHouse/ClickHouse/issues/67297). [#67326](https://github.com/ClickHouse/ClickHouse/pull/67326) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- The system table `text_log` is enabled by default. This is fully compatible with previous versions, but you may notice subtly increased disk usage on the local disk (this system table takes a tiny amount of disk space). [#67428](https://github.com/ClickHouse/ClickHouse/pull/67428) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- In previous versions, `arrayWithConstant` can be slow if asked to generate very large arrays. In the new version, it is limited to 1 GB per array. This closes [#32754](https://github.com/ClickHouse/ClickHouse/issues/32754). [#67741](https://github.com/ClickHouse/ClickHouse/pull/67741) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- Fix REPLACE modifier formatting (forbid omitting brackets). [#67774](https://github.com/ClickHouse/ClickHouse/pull/67774) ([Azat Khuzhin](https://github.com/azat)).
- Backported in [#68349](https://github.com/ClickHouse/ClickHouse/issues/68349): Reimplement `Dynamic` type. Now when the limit of dynamic data types is reached new types are not cast to String but stored in a special data structure in binary format with binary encoded data type. Now any type ever inserted into `Dynamic` column can be read from it as subcolumn. [#68132](https://github.com/ClickHouse/ClickHouse/pull/68132) ([Kruglov Pavel](https://github.com/Avogar)).

#### New Feature[​](#new-feature-4 "Direct link to New Feature")