count_distinct_* session settings

These settings are available in system.settings and are autogenerated from the ClickHouse snapshot.

count_distinct_implementation

Specifies which of the uniq* functions should be used to perform the COUNT(DISTINCT …) construction.

Possible values:

• uniq
• uniqCombined
• uniqCombined64
• uniqHLL12
• uniqExact

count_distinct_optimization

Rewrite count distinct to subquery of group by