Beta and experimental features

Because ClickHouse is open-source, it receives many contributions not only from ClickHouse employees but also from the community. These contributions are often developed at different speeds; certain features may require a lengthy prototyping phase or more time for sufficient community feedback and iteration to be considered generally available (GA).

Due to the uncertainty of when features are classified as generally available, we delineate features into two categories: Beta and Experimental.

Beta features are officially supported by the ClickHouse team. Experimental features are early prototypes driven by either the ClickHouse team or the community and aren’t officially supported.

The sections below explicitly describe the properties of Beta and Experimental features:

Beta features

Under active development to make them generally available (GA)
Main known issues can be tracked on GitHub
Functionality may change in the future
Possibly enabled in ClickHouse Cloud
The ClickHouse team supports beta features

You can find below the features considered Beta in ClickHouse Cloud and are available for use in your ClickHouse Cloud Services.

Note: please be sure to be using a current version of the ClickHouse compatibility setting to be using a recently introduced feature.

Experimental features

May never become GA
May be removed
Can introduce breaking changes
Functionality may change in the feature
Need to be deliberately enabled
The ClickHouse team doesn’t support experimental features
May lack important functionality and documentation
Can’t be enabled in the cloud

Please note: no additional experimental features are allowed to be enabled in ClickHouse Cloud other than those listed above as Beta.

Beta settings

Name	Default
compute_exact_num_defaults_for_sparse_columns	`1`
packed_skip_index_max_bytes	`1048576`
framing_output_format	`None`
enable_join_transitive_predicates	`1`
geotoh3_argument_order	`lat_lon`
optimize_trivial_count_with_sparsity_filter	`1`
enable_lightweight_update	`1`
allow_experimental_correlated_subqueries	`1`
allow_experimental_delta_lake_writes	`0`
parallel_replicas_count	`0`
parallel_replica_offset	`0`
parallel_replicas_custom_key	``
parallel_replicas_custom_key_range_lower	`0`
parallel_replicas_custom_key_range_upper	`0`
parallel_replicas_filter_pushdown	`0`
parallel_replicas_allow_view_over_mergetree	`0`
allow_experimental_database_iceberg	`0`
allow_experimental_database_unity_catalog	`0`
allow_experimental_database_glue_catalog	`0`
session_timezone	``
low_priority_query_wait_time_ms	`1000`
allow_experimental_nullable_tuple_type	`0`
ai_function_request_timeout_sec	`60`
ai_function_max_retries	`1`
ai_function_retry_initial_delay_ms	`1000`
ai_function_throw_on_error	`1`
ai_function_max_input_tokens_per_query	`1000000`
ai_function_max_output_tokens_per_query	`500000`
ai_function_max_api_calls_per_query	`1000`
ai_function_throw_on_quota_exceeded	`1`
ai_function_embedding_max_batch_size	`100`
ai_function_text_default_credentials	``
ai_function_embedding_default_credentials	``
ai_function_allow_insecure_endpoint	`0`
enable_alp_codec	`0`
allow_delta_kernel_rs	`1`
allow_insert_into_iceberg	`0`
enable_join_runtime_filters	`1`

Experimental settings

Name	Default
allow_commit_order_projection	`0`
allow_experimental_replacing_merge_with_cleanup	`0`
allow_experimental_text_index_phrase_search	`0`
allow_remote_fs_zero_copy_replication	`0`
distributed_index_analysis_min_indexes_bytes_to_activate	`1073741824`
distributed_index_analysis_min_parts_to_activate	`10`
enable_adaptive_codec_selection	`0`
enable_replacing_merge_with_cleanup_for_min_age_to_force_merge	`0`
force_read_through_cache_for_merges	`0`
merge_selector_algorithm	`Simple`
merge_selector_heuristic_to_lower_max_parts_to_merge_at_once_exponent	`5`
notify_newest_block_number	`0`
part_moves_between_shards_delay_seconds	`30`
part_moves_between_shards_enable	`0`
remote_fs_zero_copy_path_compatible_mode	`0`
remote_fs_zero_copy_zookeeper_path	`/clickhouse/zero_copy`
remove_rolled_back_parts_immediately	`1`
use_reader_executor	`0`
reader_executor_use_long_connections	`0`
reader_executor_min_bytes_for_seek	`2097152`
reader_executor_max_tail_for_drain	`1048576`
reader_executor_window_size	`4194304`
reader_executor_block_size	`1048576`
group_by_top_k_optimization_observation_rows	`65536`
query_plan_optimize_join_order_max_searched_plans	`100000`
query_plan_optimize_join_order_randomize	`0`
ast_fuzzer_runs	`0`
ast_fuzzer_any_query	`0`
ast_fuzzer_oracle	`0`
allow_fuzz_query_functions	`0`
reserve_memory	`0`
resumable_backup_from_snapshot	`0`
allow_experimental_url_wildcard_from_index_pages	`0`
enable_materialized_cte	`0`
analyzer_inline_views	`0`
allow_experimental_kafka_offsets_storage_in_keeper	`0`
automatic_parallel_replicas_mode	`0`
automatic_parallel_replicas_min_bytes_per_replica	`1048576`
parallel_replicas_plan_based	`0`
distributed_index_analysis	`0`
allow_experimental_materialized_postgresql_table	`0`
allow_experimental_funnel_functions	`0`
allow_experimental_nlp_functions	`0`
allow_experimental_hash_functions	`0`
allow_experimental_time_series_table	`0`
time_series_prefer_recent_samples_table	`1`
unique_key_max_encoded_size	`256`
unique_key_probe_implementation	`auto`
allow_experimental_unique_key	`0`
enable_quantized_codec	`0`
enable_sz3_codec	`0`
enable_zxc_codec	`0`
throw_on_unsupported_query_inside_transaction	`1`
wait_changes_become_visible_after_commit_mode	`wait_unknown`
implicit_transaction	`0`
grace_hash_join_initial_buckets	`1`
grace_hash_join_max_buckets	`1024`
join_to_sort_minimum_perkey_rows	`40`
join_to_sort_maximum_table_rows	`10000`
allow_experimental_join_right_table_sorting	`0`
allow_experimental_json_lazy_type_hints	`0`
enable_streaming_queries	`0`
stop_refreshable_materialized_views_on_startup	`0`
allow_experimental_database_materialized_postgresql	`0`
allow_experimental_database_hms_catalog	`0`
allow_experimental_kusto_dialect	`0`
allow_experimental_prql_dialect	`0`
allow_experimental_polyglot_dialect	`0`
enable_json_ast_dialect	`0`
polyglot_dialect	``
enable_adaptive_memory_spill_scheduler	`0`
allow_experimental_cleanup_old_data_files_compaction	`0`
allow_experimental_iceberg_compaction	`0`
iceberg_manifest_min_count_to_compact	`30`
allow_iceberg_remove_orphan_files	`0`
iceberg_orphan_files_older_than_seconds	`259200`
allow_experimental_expire_snapshots	`0`
write_full_path_in_iceberg_metadata	`0`
iceberg_metadata_compression_method	``
make_distributed_plan	`0`
distributed_plan_execute_locally	`0`
distributed_plan_default_shuffle_join_bucket_count	`8`
distributed_plan_default_reader_bucket_count	`8`
distributed_plan_workers_num	`0`
distributed_plan_workers_provisioning_timeout_ms	`10000`
distributed_plan_force_exchange_kind	``
distributed_plan_max_rows_to_broadcast	`20000`
distributed_plan_prefer_replicas_over_workers	`0`
allow_experimental_ytsaurus_table_engine	`0`
allow_experimental_ytsaurus_table_function	`0`
allow_experimental_ytsaurus_dictionary_source	`0`
distributed_plan_force_shuffle_aggregation	`0`
enable_cascades_optimizer	`0`
join_runtime_filter_exact_values_limit	`10000`
join_runtime_bloom_filter_bytes	`524288`
join_runtime_bloom_filter_hash_functions	`3`
join_runtime_filter_pass_ratio_threshold_for_disabling	`0.7`
join_runtime_filter_blocks_to_skip_before_reenabling	`30`
join_runtime_bloom_filter_max_ratio_of_set_bits	`0.7`
join_runtime_filter_min_probe_rows	`1000`
enable_join_runtime_filters_index_analysis	`0`
rewrite_in_to_join	`0`
allow_experimental_time_series_aggregate_functions	`0`
promql_database	``
promql_table	``
promql_evaluation_time	`auto`
allow_experimental_paimon_storage_engine	`0`
paimon_target_snapshot_id	`-1`
max_consume_snapshots	`0`
use_paimon_partition_pruning	`0`
allow_experimental_object_storage_queue_hive_partitioning	`0`
query_plan_optimize_join_order_algorithm	`greedy`
allow_experimental_database_paimon_rest_catalog	`0`
webassembly_udf_max_fuel	`100000`
webassembly_udf_max_memory	`134217728`
webassembly_udf_max_input_block_size	`0`
webassembly_udf_max_instances	`32`
allow_experimental_eval_table_function	`0`