https://gh-api.clickhouse.tech/play?user=play#U0VMRUNUIHRvU3RhcnRPZk1vbnRoKGNyZWF0ZWRfYXQpIEFTIGRhdGUsIGNvdW50KCksIHVuaXEoYWN0b3JfbG9naW4pIEFTIHUsIGJhcih1LCAwLCAxMDAwLCAxMDApIEZST00gZ2l0aHViX2V2ZW50cyAKV0hFUkUgcmVwb19uYW1lIElOICgneWFuZGV4L0NsaWNrSG91c2UnLCAnQ2xpY2tIb3VzZS9DbGlja0hvdXNlJykgCiAgQU5EIGV2ZW50X3R5cGUgPSAnSXNzdWVDb21tZW50RXZlbnQnCiAgQU5EIGFjdG9yX2xvZ2luIE5PVCBMSUtFICdyb2JvdC0lJyBBTkQgYWN0b3JfbG9naW4gTk9UIExJS0UgJyVbYm90XScKR1JPVVAgQlkgZGF0ZSBPUkRFUiBCWSBkYXRl

```
SELECT toStartOfMonth(created_at) AS date, count(), uniq(actor_login) AS u, bar(u, 0, 1000, 100) FROM github_events 
WHERE repo_name IN ('yandex/ClickHouse', 'ClickHouse/ClickHouse') 
  AND event_type = 'IssueCommentEvent'
  AND actor_login NOT LIKE 'robot-%' AND actor_login NOT LIKE '%[bot]'
GROUP BY date ORDER BY date
```

```
Code: 44. DB::Exception: Cannot convert column ColumnLowCardinality to mask.: while executing 'FUNCTION and(notLike(actor_login, 'robot-%') :: 3, notLike(actor_login, '%[bot]') :: 1) -> and(notLike(actor_login, 'robot-%'), notLike(actor_login, '%[bot]')) UInt8 : 2': While executing MergeTreeThread. (ILLEGAL_COLUMN) (version 21.11.1.8052 (official build))
```
M(TotalsMode, totals_mode, TotalsMode::AFTER_HAVING_EXCLUSIVE, "How to calculate TOTALS when HAVING is present, as well as when max_rows_to_group_by and group_by_overflow_mode = ‘any’ are present.", IMPORTANT) \
    M(Float, totals_auto_threshold, 0.5, "The threshold for totals_mode = 'auto'.", 0) \
    \
    M(Bool, allow_suspicious_low_cardinality_types, false, "In CREATE TABLE statement allows specifying LowCardinality modifier for types of small fixed size (8 or less). Enabling this may increase merge times and memory consumption.", 0) \
    M(Bool, compile_expressions, true, "Compile some scalar functions and operators to native code.", 0) \
    M(UInt64, min_count_to_compile_expression, 3, "The number of identical expressions before they are JIT-compiled", 0) \
    M(Bool, compile_aggregate_expressions, true, "Compile aggregate functions to native code.", 0) \
    M(UInt64, min_count_to_compile_aggregate_expression, 3, "The number of identical aggregate expressions before they are JIT-compiled", 0) \
    M(UInt64, group_by_two_level_threshold, 100000, "From what number of keys, a two-level aggregation starts. 0 - the threshold is not set.", 0) \
    M(UInt64, group_by_two_level_threshold_bytes, 50000000, "From what size of the aggregation state in bytes, a two-level aggregation begins to be used. 0 - the threshold is not set. Two-level aggregation is used when at least one of the thresholds is triggered.", 0) \
    M(Bool, distributed_aggregation_memory_efficient, true, "Is the memory-saving mode of distributed aggregation enabled.", 0) \
    M(UInt64, aggregation_memory_efficient_merge_threads, 0, "Number of threads to use for merge intermediate aggregation results in memory efficient mode. When bigger, then more memory is consumed. 0 means - same as 'max_threads'.", 0) \
    M(Bool, enable_positional_arguments, false, "Enable positional arguments in ORDER BY, GROUP BY and LIMIT BY", 0) \
    \
    M(UInt64, max_parallel_replicas, 1, "The maximum number of replicas of each shard used when the query is executed. For consistency (to get different parts of the same partition), this option only works for the specified sampling key. The lag of the replicas is not controlled.", 0) \
    M(UInt64, parallel_replicas_count, 0, "", 0) \
    M(UInt64, parallel_replica_offset, 0, "", 0) \
    \
    M(Bool, skip_unavailable_shards, false, "If true, ClickHouse silently skips unavailable shards and nodes unresolvable through DNS. Shard is marked as unavailable when none of the replicas can be reached.", 0) \
    \
    M(UInt64, parallel_distributed_insert_select, 0, "Process distributed INSERT SELECT query in the same cluster on local tables on every shard, if 1 SELECT is executed on each shard, if 2 SELECT and INSERT is executed on each shard", 0) \
    M(UInt64, distributed_group_by_no_merge, 0, "If 1, Do not merge aggregation states from different servers for distributed queries (shards will process query up to the Complete stage, initiator just proxies the data from the shards). If 2 the initiator will apply ORDER BY and LIMIT stages (it is not in case when shard process query up to the Complete stage)", 0) \
    M(UInt64, distributed_push_down_limit, 1, "If 1, LIMIT will be applied on each shard separatelly. Usually you don't need to use it, since this will be done automatically if it is possible, i.e. for simple query SELECT FROM LIMIT.", 0) \
    M(Bool, optimize_distributed_group_by_sharding_key, true, "Optimize GROUP BY sharding_key queries (by avoiding costly aggregation on the initiator server).", 0) \
    M(UInt64, optimize_skip_unused_shards_limit, 1000, "Limit for number of sharding key values, turns off optimize_skip_unused_shards if the limit is reached", 0) \
    M(Bool, optimize_skip_unused_shards, false, "Assumes that data is distributed by sharding_key. Optimization to skip unused shards if SELECT query filters by sharding_key.", 0) \
    M(Bool, optimize_skip_unused_shards_rewrite_in, true, "Rewrite IN in query for remote shards to exclude values that does not belong to the shard (requires optimize_skip_unused_shards)", 0) \
    M(Bool, allow_nondeterministic_optimize_skip_unused_shards, false, "Allow non-deterministic functions (includes dictGet) in sharding_key for optimize_skip_unused_shards", 0) \
    M(UInt64, force_optimize_skip_unused_shards, 0, "Throw an exception if unused shards cannot be skipped (1 - throw only if the table has the sharding key, 2 - always throw.", 0) \
    M(UInt64, optimize_skip_unused_shards_nesting, 0, "Same as optimize_skip_unused_shards, but accept nesting level until which it will work.", 0) \