Optimize data on INSERT

Fixed unsafe assignment to a reference in InterpreterSelectWithUnionQuery::InterpreterSelectWithUnionQuery()

Fix access rights required for the merge() table function.

Do not pass -fsanitize-blacklist for gcc (it does not support it) for UBSAN

Build utils in CI, at least in split build

ReadFloat 8digits unroll performance improvement

Adaptive choose of single/multi part upload in WriteBufferFromS3

Fix 01600_remerge_sort_lowered_memory_bytes_ratio flap

CreateQuery create as select with columns specification

Fixed `std::out_of_range: basic_string` in S3 URL parsing

Currently we don't build them at all, so they were broken by https://github.com/ClickHouse/ClickHouse/pull/17988

Docker cli example

Remove test_keeper_server in perf tests

Allow Atomic database inside MaterializeMySQL

Add changelog for 20.12

Array aggregation functions

Fix possible corruption in librdkafka snappy decompression

MemoryStorage read optimization

Remove obsolete settings