> ## Documentation Index
> Fetch the complete documentation index at: https://private-7c7dfe99-fix-nav-issues.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.
# Beta and experimental features
> ClickHouse has beta and experimental features. This documentation page discusses definition.
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](/reference/settings/session-settings#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.
{/*AUTOGENERATED_START*/}
Beta settings
| Name | Default |
| ------------------------------------------------------------------------------------------------------------------------------------ | --------- |
| [enable\_join\_transitive\_predicates](/reference/settings/session-settings#enable_join_transitive_predicates) | `1` |
| [geotoh3\_argument\_order](/reference/settings/session-settings#geotoh3_argument_order) | `lat_lon` |
| [enable\_lightweight\_update](/reference/settings/session-settings#enable_lightweight_update) | `1` |
| [allow\_experimental\_correlated\_subqueries](/reference/settings/session-settings#allow_experimental_correlated_subqueries) | `1` |
| [parallel\_replicas\_count](/reference/settings/session-settings#parallel_replicas_count) | `0` |
| [parallel\_replica\_offset](/reference/settings/session-settings#parallel_replica_offset) | `0` |
| [parallel\_replicas\_custom\_key](/reference/settings/session-settings#parallel_replicas_custom_key) | \`\` |
| [parallel\_replicas\_custom\_key\_range\_lower](/reference/settings/session-settings#parallel_replicas_custom_key_range_lower) | `0` |
| [parallel\_replicas\_custom\_key\_range\_upper](/reference/settings/session-settings#parallel_replicas_custom_key_range_upper) | `0` |
| [parallel\_replicas\_filter\_pushdown](/reference/settings/session-settings#parallel_replicas_filter_pushdown) | `0` |
| [parallel\_replicas\_allow\_view\_over\_mergetree](/reference/settings/session-settings#parallel_replicas_allow_view_over_mergetree) | `0` |
| [allow\_experimental\_database\_iceberg](/reference/settings/session-settings#allow_experimental_database_iceberg) | `0` |
| [allow\_experimental\_database\_unity\_catalog](/reference/settings/session-settings#allow_experimental_database_unity_catalog) | `0` |
| [allow\_experimental\_database\_glue\_catalog](/reference/settings/session-settings#allow_experimental_database_glue_catalog) | `0` |
| [session\_timezone](/reference/settings/session-settings#session_timezone) | \`\` |
| [low\_priority\_query\_wait\_time\_ms](/reference/settings/session-settings#low_priority_query_wait_time_ms) | `1000` |
| [allow\_experimental\_nullable\_tuple\_type](/reference/settings/session-settings#allow_experimental_nullable_tuple_type) | `0` |
| [allow\_experimental\_delta\_kernel\_rs](/reference/settings/session-settings#allow_experimental_delta_kernel_rs) | `1` |
| [allow\_insert\_into\_iceberg](/reference/settings/session-settings#allow_insert_into_iceberg) | `0` |
| [enable\_join\_runtime\_filters](/reference/settings/session-settings#enable_join_runtime_filters) | `1` |
Experimental settings
| Name | Default |
| ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------- |
| [allow\_commit\_order\_projection](/reference/settings/merge-tree-settings#allow_commit_order_projection) | `0` |
| [allow\_experimental\_replacing\_merge\_with\_cleanup](/reference/settings/merge-tree-settings#allow_experimental_replacing_merge_with_cleanup) | `0` |
| [allow\_remote\_fs\_zero\_copy\_replication](/reference/settings/merge-tree-settings#allow_remote_fs_zero_copy_replication) | `0` |
| [distributed\_index\_analysis\_min\_indexes\_bytes\_to\_activate](/reference/settings/merge-tree-settings#distributed_index_analysis_min_indexes_bytes_to_activate) | `1073741824` |
| [distributed\_index\_analysis\_min\_parts\_to\_activate](/reference/settings/merge-tree-settings#distributed_index_analysis_min_parts_to_activate) | `10` |
| [enable\_replacing\_merge\_with\_cleanup\_for\_min\_age\_to\_force\_merge](/reference/settings/merge-tree-settings#enable_replacing_merge_with_cleanup_for_min_age_to_force_merge) | `0` |
| [force\_read\_through\_cache\_for\_merges](/reference/settings/merge-tree-settings#force_read_through_cache_for_merges) | `0` |
| [merge\_selector\_algorithm](/reference/settings/merge-tree-settings#merge_selector_algorithm) | `Simple` |
| [merge\_selector\_enable\_heuristic\_to\_lower\_max\_parts\_to\_merge\_at\_once](/reference/settings/merge-tree-settings#merge_selector_enable_heuristic_to_lower_max_parts_to_merge_at_once) | `0` |
| [merge\_selector\_heuristic\_to\_lower\_max\_parts\_to\_merge\_at\_once\_exponent](/reference/settings/merge-tree-settings#merge_selector_heuristic_to_lower_max_parts_to_merge_at_once_exponent) | `5` |
| [notify\_newest\_block\_number](/reference/settings/merge-tree-settings#notify_newest_block_number) | `0` |
| [packed\_skip\_index\_max\_bytes](/reference/settings/merge-tree-settings#packed_skip_index_max_bytes) | `0` |
| [part\_moves\_between\_shards\_delay\_seconds](/reference/settings/merge-tree-settings#part_moves_between_shards_delay_seconds) | `30` |
| [part\_moves\_between\_shards\_enable](/reference/settings/merge-tree-settings#part_moves_between_shards_enable) | `0` |
| [remote\_fs\_zero\_copy\_path\_compatible\_mode](/reference/settings/merge-tree-settings#remote_fs_zero_copy_path_compatible_mode) | `0` |
| [remote\_fs\_zero\_copy\_zookeeper\_path](/reference/settings/merge-tree-settings#remote_fs_zero_copy_zookeeper_path) | `/clickhouse/zero_copy` |
| [remove\_rolled\_back\_parts\_immediately](/reference/settings/merge-tree-settings#remove_rolled_back_parts_immediately) | `1` |
| [shared\_merge\_tree\_virtual\_parts\_discovery\_batch](/reference/settings/merge-tree-settings#shared_merge_tree_virtual_parts_discovery_batch) | `1` |
| [use\_reader\_executor](/reference/settings/session-settings#use_reader_executor) | `0` |
| [query\_plan\_optimize\_join\_order\_max\_searched\_plans](/reference/settings/session-settings#query_plan_optimize_join_order_max_searched_plans) | `100000` |
| [query\_plan\_optimize\_join\_order\_randomize](/reference/settings/session-settings#query_plan_optimize_join_order_randomize) | `0` |
| [ast\_fuzzer\_runs](/reference/settings/session-settings#ast_fuzzer_runs) | `0` |
| [ast\_fuzzer\_any\_query](/reference/settings/session-settings#ast_fuzzer_any_query) | `0` |
| [allow\_fuzz\_query\_functions](/reference/settings/session-settings#allow_fuzz_query_functions) | `0` |
| [enable\_materialized\_cte](/reference/settings/session-settings#enable_materialized_cte) | `0` |
| [analyzer\_inline\_views](/reference/settings/session-settings#analyzer_inline_views) | `0` |
| [allow\_experimental\_kafka\_offsets\_storage\_in\_keeper](/reference/settings/session-settings#allow_experimental_kafka_offsets_storage_in_keeper) | `0` |
| [allow\_experimental\_delta\_lake\_writes](/reference/settings/session-settings#allow_experimental_delta_lake_writes) | `0` |
| [automatic\_parallel\_replicas\_mode](/reference/settings/session-settings#automatic_parallel_replicas_mode) | `0` |
| [automatic\_parallel\_replicas\_min\_bytes\_per\_replica](/reference/settings/session-settings#automatic_parallel_replicas_min_bytes_per_replica) | `1048576` |
| [distributed\_index\_analysis](/reference/settings/session-settings#distributed_index_analysis) | `0` |
| [allow\_experimental\_materialized\_postgresql\_table](/reference/settings/session-settings#allow_experimental_materialized_postgresql_table) | `0` |
| [allow\_experimental\_funnel\_functions](/reference/settings/session-settings#allow_experimental_funnel_functions) | `0` |
| [allow\_experimental\_nlp\_functions](/reference/settings/session-settings#allow_experimental_nlp_functions) | `0` |
| [allow\_experimental\_hash\_functions](/reference/settings/session-settings#allow_experimental_hash_functions) | `0` |
| [allow\_experimental\_time\_series\_table](/reference/settings/session-settings#allow_experimental_time_series_table) | `0` |
| [unique\_key\_max\_encoded\_size](/reference/settings/session-settings#unique_key_max_encoded_size) | `256` |
| [allow\_experimental\_unique\_key](/reference/settings/session-settings#allow_experimental_unique_key) | `0` |
| [allow\_experimental\_codecs](/reference/settings/session-settings#allow_experimental_codecs) | `0` |
| [throw\_on\_unsupported\_query\_inside\_transaction](/reference/settings/session-settings#throw_on_unsupported_query_inside_transaction) | `1` |
| [wait\_changes\_become\_visible\_after\_commit\_mode](/reference/settings/session-settings#wait_changes_become_visible_after_commit_mode) | `wait_unknown` |
| [implicit\_transaction](/reference/settings/session-settings#implicit_transaction) | `0` |
| [grace\_hash\_join\_initial\_buckets](/reference/settings/session-settings#grace_hash_join_initial_buckets) | `1` |
| [grace\_hash\_join\_max\_buckets](/reference/settings/session-settings#grace_hash_join_max_buckets) | `1024` |
| [join\_to\_sort\_minimum\_perkey\_rows](/reference/settings/session-settings#join_to_sort_minimum_perkey_rows) | `40` |
| [join\_to\_sort\_maximum\_table\_rows](/reference/settings/session-settings#join_to_sort_maximum_table_rows) | `10000` |
| [allow\_experimental\_join\_right\_table\_sorting](/reference/settings/session-settings#allow_experimental_join_right_table_sorting) | `0` |
| [allow\_experimental\_json\_lazy\_type\_hints](/reference/settings/session-settings#allow_experimental_json_lazy_type_hints) | `0` |
| [enable\_streaming\_queries](/reference/settings/session-settings#enable_streaming_queries) | `0` |
| [allow\_experimental\_text\_index\_lazy\_apply](/reference/settings/session-settings#allow_experimental_text_index_lazy_apply) | `0` |
| [allow\_experimental\_window\_view](/reference/settings/session-settings#allow_experimental_window_view) | `0` |
| [window\_view\_clean\_interval](/reference/settings/session-settings#window_view_clean_interval) | `60` |
| [window\_view\_heartbeat\_interval](/reference/settings/session-settings#window_view_heartbeat_interval) | `15` |
| [wait\_for\_window\_view\_fire\_signal\_timeout](/reference/settings/session-settings#wait_for_window_view_fire_signal_timeout) | `10` |
| [stop\_refreshable\_materialized\_views\_on\_startup](/reference/settings/session-settings#stop_refreshable_materialized_views_on_startup) | `0` |
| [allow\_experimental\_database\_materialized\_postgresql](/reference/settings/session-settings#allow_experimental_database_materialized_postgresql) | `0` |
| [allow\_experimental\_query\_deduplication](/reference/settings/session-settings#allow_experimental_query_deduplication) | `0` |
| [allow\_experimental\_database\_hms\_catalog](/reference/settings/session-settings#allow_experimental_database_hms_catalog) | `0` |
| [allow\_experimental\_kusto\_dialect](/reference/settings/session-settings#allow_experimental_kusto_dialect) | `0` |
| [allow\_experimental\_prql\_dialect](/reference/settings/session-settings#allow_experimental_prql_dialect) | `0` |
| [allow\_experimental\_polyglot\_dialect](/reference/settings/session-settings#allow_experimental_polyglot_dialect) | `0` |
| [polyglot\_dialect](/reference/settings/session-settings#polyglot_dialect) | \`\` |
| [enable\_adaptive\_memory\_spill\_scheduler](/reference/settings/session-settings#enable_adaptive_memory_spill_scheduler) | `0` |
| [allow\_experimental\_cleanup\_old\_data\_files\_compaction](/reference/settings/session-settings#allow_experimental_cleanup_old_data_files_compaction) | `0` |
| [allow\_experimental\_iceberg\_compaction](/reference/settings/session-settings#allow_experimental_iceberg_compaction) | `0` |
| [allow\_iceberg\_remove\_orphan\_files](/reference/settings/session-settings#allow_iceberg_remove_orphan_files) | `0` |
| [iceberg\_orphan\_files\_older\_than\_seconds](/reference/settings/session-settings#iceberg_orphan_files_older_than_seconds) | `259200` |
| [allow\_experimental\_expire\_snapshots](/reference/settings/session-settings#allow_experimental_expire_snapshots) | `0` |
| [write\_full\_path\_in\_iceberg\_metadata](/reference/settings/session-settings#write_full_path_in_iceberg_metadata) | `0` |
| [iceberg\_metadata\_compression\_method](/reference/settings/session-settings#iceberg_metadata_compression_method) | \`\` |
| [make\_distributed\_plan](/reference/settings/session-settings#make_distributed_plan) | `0` |
| [distributed\_plan\_execute\_locally](/reference/settings/session-settings#distributed_plan_execute_locally) | `0` |
| [distributed\_plan\_default\_shuffle\_join\_bucket\_count](/reference/settings/session-settings#distributed_plan_default_shuffle_join_bucket_count) | `8` |
| [distributed\_plan\_default\_reader\_bucket\_count](/reference/settings/session-settings#distributed_plan_default_reader_bucket_count) | `8` |
| [distributed\_plan\_force\_exchange\_kind](/reference/settings/session-settings#distributed_plan_force_exchange_kind) | \`\` |
| [distributed\_plan\_max\_rows\_to\_broadcast](/reference/settings/session-settings#distributed_plan_max_rows_to_broadcast) | `20000` |
| [distributed\_plan\_prefer\_replicas\_over\_workers](/reference/settings/session-settings#distributed_plan_prefer_replicas_over_workers) | `0` |
| [allow\_experimental\_ytsaurus\_table\_engine](/reference/settings/session-settings#allow_experimental_ytsaurus_table_engine) | `0` |
| [allow\_experimental\_ytsaurus\_table\_function](/reference/settings/session-settings#allow_experimental_ytsaurus_table_function) | `0` |
| [allow\_experimental\_ytsaurus\_dictionary\_source](/reference/settings/session-settings#allow_experimental_ytsaurus_dictionary_source) | `0` |
| [distributed\_plan\_force\_shuffle\_aggregation](/reference/settings/session-settings#distributed_plan_force_shuffle_aggregation) | `0` |
| [join\_runtime\_filter\_exact\_values\_limit](/reference/settings/session-settings#join_runtime_filter_exact_values_limit) | `10000` |
| [join\_runtime\_bloom\_filter\_bytes](/reference/settings/session-settings#join_runtime_bloom_filter_bytes) | `524288` |
| [join\_runtime\_bloom\_filter\_hash\_functions](/reference/settings/session-settings#join_runtime_bloom_filter_hash_functions) | `3` |
| [join\_runtime\_filter\_pass\_ratio\_threshold\_for\_disabling](/reference/settings/session-settings#join_runtime_filter_pass_ratio_threshold_for_disabling) | `0.7` |
| [join\_runtime\_filter\_blocks\_to\_skip\_before\_reenabling](/reference/settings/session-settings#join_runtime_filter_blocks_to_skip_before_reenabling) | `30` |
| [join\_runtime\_bloom\_filter\_max\_ratio\_of\_set\_bits](/reference/settings/session-settings#join_runtime_bloom_filter_max_ratio_of_set_bits) | `0.7` |
| [rewrite\_in\_to\_join](/reference/settings/session-settings#rewrite_in_to_join) | `0` |
| [allow\_experimental\_time\_series\_aggregate\_functions](/reference/settings/session-settings#allow_experimental_time_series_aggregate_functions) | `0` |
| [promql\_database](/reference/settings/session-settings#promql_database) | \`\` |
| [promql\_table](/reference/settings/session-settings#promql_table) | \`\` |
| [promql\_evaluation\_time](/reference/settings/session-settings#promql_evaluation_time) | `auto` |
| [allow\_experimental\_paimon\_storage\_engine](/reference/settings/session-settings) | `0` |
| [paimon\_target\_snapshot\_id](/reference/settings/session-settings) | `-1` |
| [max\_consume\_snapshots](/reference/settings/session-settings) | `0` |
| [use\_paimon\_partition\_pruning](/reference/settings/session-settings#use_paimon_partition_pruning) | `0` |
| [allow\_experimental\_object\_storage\_queue\_hive\_partitioning](/reference/settings/session-settings#allow_experimental_object_storage_queue_hive_partitioning) | `0` |
| [query\_plan\_optimize\_join\_order\_algorithm](/reference/settings/session-settings#query_plan_optimize_join_order_algorithm) | `greedy` |
| [allow\_experimental\_database\_paimon\_rest\_catalog](/reference/settings/session-settings#allow_experimental_database_paimon_rest_catalog) | `0` |
| [webassembly\_udf\_max\_fuel](/reference/settings/session-settings#webassembly_udf_max_fuel) | `100000` |
| [webassembly\_udf\_max\_memory](/reference/settings/session-settings#webassembly_udf_max_memory) | `134217728` |
| [webassembly\_udf\_max\_input\_block\_size](/reference/settings/session-settings#webassembly_udf_max_input_block_size) | `0` |
| [webassembly\_udf\_max\_instances](/reference/settings/session-settings#webassembly_udf_max_instances) | `32` |
| [allow\_experimental\_ai\_functions](/reference/settings/session-settings#allow_experimental_ai_functions) | `0` |
| [ai\_function\_credentials](/reference/settings/session-settings#ai_function_credentials) | \`\` |
| [ai\_function\_request\_timeout\_sec](/reference/settings/session-settings#ai_function_request_timeout_sec) | `60` |
| [ai\_function\_max\_retries](/reference/settings/session-settings#ai_function_max_retries) | `0` |
| [ai\_function\_retry\_initial\_delay\_ms](/reference/settings/session-settings#ai_function_retry_initial_delay_ms) | `1000` |
| [ai\_function\_throw\_on\_error](/reference/settings/session-settings#ai_function_throw_on_error) | `1` |
| [ai\_function\_max\_input\_tokens\_per\_query](/reference/settings/session-settings#ai_function_max_input_tokens_per_query) | `1000000` |
| [ai\_function\_max\_output\_tokens\_per\_query](/reference/settings/session-settings#ai_function_max_output_tokens_per_query) | `500000` |
| [ai\_function\_max\_api\_calls\_per\_query](/reference/settings/session-settings#ai_function_max_api_calls_per_query) | `0` |
| [ai\_function\_throw\_on\_quota\_exceeded](/reference/settings/session-settings#ai_function_throw_on_quota_exceeded) | `1` |
| [ai\_function\_embedding\_max\_batch\_size](/reference/settings/session-settings#ai_function_embedding_max_batch_size) | `100` |