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* Suppport for cascaded materialized views. [#6324](https://github.com/yandex/ClickHouse/pull/6324) ([Amos Bird](https://github.com/amosbird))
* Turn on query profiler by default to sample every query execution thread once a second. [#6283](https://github.com/yandex/ClickHouse/pull/6283) ([alexey-milovidov](https://github.com/alexey-milovidov))
* Input format `ORC`. [#6454](https://github.com/yandex/ClickHouse/pull/6454) ([akonyaev90](https://github.com/akonyaev90))
* Using `FastOps` library for functions `exp`, `log`, `sigmoid`, `tanh`. Added two new functions: `sigmoid` and `tanh`. FastOps is a fast vector math library from Michael Parakhin (Yandex CTO). Improved performance of `exp` and `log` functions more than 6 times. The functions `exp` and `log` from `Float32` argument will return `Float32` (in previous versions they always return `Float64`). Now `exp(nan)` may return `inf`. The result of `exp` and `log` functions may be not the nearest machine representable number to the true answer. [#6254](https://github.com/yandex/ClickHouse/pull/6254) ([alexey-milovidov](https://github.com/alexey-milovidov))
* Added two new functions: `sigmoid` and `tanh` (that are useful for machine learning applications). [#6254](https://github.com/yandex/ClickHouse/pull/6254) ([alexey-milovidov]
* Function `hasToken(haystack, token)`, `hasTokenCaseInsensitive(haystack, token)` to check if given token is in haystack. Token is a maximal length substring between two non alphanumeric ASCII characters (or boundaries of haystack). Token must be a constant string. Supported by tokenbf_v1 index specialization. [#6596](https://github.com/yandex/ClickHouse/pull/6596), [#6662](https://github.com/yandex/ClickHouse/pull/6662) ([Vasily Nemkov](https://github.com/Enmk))
* New function `neighbor(value, offset[, default_value])`. Allows to reach prev/next value within column in a block of data. [#5925](https://github.com/yandex/ClickHouse/pull/5925) ([Alex Krash](https://github.com/alex-krash)) [6685365ab8c5b74f9650492c88a012596eb1b0c6](https://github.com/yandex/ClickHouse/commit/6685365ab8c5b74f9650492c88a012596eb1b0c6) [341e2e4587a18065c2da1ca888c73389f48ce36c](https://github.com/yandex/ClickHouse/commit/341e2e4587a18065c2da1ca888c73389f48ce36c) [Alexey Milovidov](https://github.com/alexey-milovidov)
* Created a function `currentUser()`, returning login of authorized user. Added alias `user()` for compatibility with MySQL. [#6470](https://github.com/yandex/ClickHouse/pull/6470) ([Alex Krash](https://github.com/alex-krash))
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### Performance Improvement
* Optimize queries with `ORDER BY expressions` clause, where `expressions` have coinciding prefix with sorting key in `MergeTree` tables. This optimization is enabled with `optimize_read_in_order` setting. [#6054](https://github.com/yandex/ClickHouse/pull/6054) [#6629](https://github.com/yandex/ClickHouse/pull/6629) ([Anton Popov](https://github.com/CurtizJ))
* Implemented batch variant of updating aggregate function states. It may lead to performance benefits. [#6435](https://github.com/yandex/ClickHouse/pull/6435) ([alexey-milovidov](https://github.com/alexey-milovidov))
* Using `FastOps` library for functions `exp`, `log`, `sigmoid`, `tanh`. FastOps is a fast vector math library from Michael Parakhin (Yandex CTO). Improved performance of `exp` and `log` functions more than 6 times. The functions `exp` and `log` from `Float32` argument will return `Float32` (in previous versions they always return `Float64`). Now `exp(nan)` may return `inf`. The result of `exp` and `log` functions may be not the nearest machine representable number to the true answer. [#6254](https://github.com/yandex/ClickHouse/pull/6254) ([alexey-milovidov](https://github.com/alexey-milovidov))
* Disable consecutive key optimization for `UInt8/16`. [#6298](https://github.com/yandex/ClickHouse/pull/6298) [#6701](https://github.com/yandex/ClickHouse/pull/6701) ([akuzm](https://github.com/akuzm))
* Slightly improve performance of `MemoryTracker`. [#6653](https://github.com/yandex/ClickHouse/pull/6653) ([alexey-milovidov](https://github.com/alexey-milovidov))
* Allow to use multiple threads during parts loading and removal. [#6372](https://github.com/yandex/ClickHouse/issues/6372) [#6074](https://github.com/yandex/ClickHouse/issues/6074) [#6438](https://github.com/yandex/ClickHouse/pull/6438) ([alexey-milovidov](https://github.com/alexey-milovidov))