Reserved Engine Variables

The following engine variables are currently reserved for internal use only:

Variable Name	Note
`activity_tracking_id`
`aggregator_id`
`allow_point_in_time_attach`
`allow_unsafe_bottomless_commands`
`allow_unsupported_filesystem`
`alter_signal_timeout`
`analyze_batch_size`
`as_aggregator`
`as_leaf`
`attach_force_skip_execution_errors`
`attach_rebalance_delay_seconds`
`auditlogsdir`
`auto_attach`
`auto_increment_increment`
`auto_increment_offset`
`auto_replicate`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`back_log`
`background_statistics_collection_interval`
`background_statistics_collection_threshold`
`backup_signal_timeout`
`binary_serialization`
`bind_address`
`blob_cache_sync_interval`
`bottomless_cloud_debug_tracing`
`bottomless_incremental_autostats_collection_threshold`
`bottomless_storage_location`
`buffered_rows`
`change_count_write_interval`
`character_set_client`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`character_set_connection`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`character_set_database`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`character_set_filesystem`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`character_set_results`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`character_set_system`	The character set used to store identifiers. The value is read-only and always has the value `utf8`.
`clamp_histogram_date_estimates`
`clear_orphan_databases_on_attach`
`cloud_permissions`
`columnar_segment_rows`	Deprecated alias to `columnstore_segment_rows`.
`columnstore_disk_insert_threshold`
`columnstore_json_trace_schema`
`columnstore_row_value_table_lock_threshold`
`columnstore_sample_per_partition_limit`
`columnstore_small_blob_combination_threshold`
`command_loop`
`compile_metadata_parallel`
`convert_nonunique_hash_to_skiplist`
`date_format`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`datetime_format`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`datetime_precision_mode`
`deadlock_avoidance_strategy`
`debug`
`debug_mode`
`default_autostats_columnstore_cardinality_mode`
`default_autostats_columnstore_sampling`
`default_autostats_histogram_mode`
`default_autostats_rowstore_cardinality_mode`
`default_columnstore_table_lock_threshold`
`default_max_histogram_buckets`
`default_spill_dependent_outputters`
`default_week_format`
`defaults_file`
`disable_cluster_variables`
`disable_general_logging`
`disable_histogram_estimation`
`disable_sampling_estimation`
`disable_sampling_estimation_with_histograms`
`disable_subquery_merge_with_straight_joins`
`disable_update_delete_distributed_transactions`
`display_full_estimation_stats`
`distributed_connect_timeout`
`distributed_heartbeat_timeout`
`distributed_optimizer_estimated_restricted_search_cost_bound`
`distributed_optimizer_max_join_size`
`distributed_optimizer_min_join_size_run_initial_heuristics`
`distributed_optimizer_nodes`
`distributed_optimizer_old_selectivity_table_threshold`
`distributed_optimizer_run_legacy_heuristic`
`distributed_optimizer_selectivity_fallback_threshold`
`distributed_optimizer_unrestricted_search_threshold`
`distributed_optimizer_verbose`
`div_precision_increment`
`dont_convert_error_rolled_back_xact`
`durability`
`enable_auto_profile`
`enable_background_flusher`	By setting the value of this variable to `0`, the background flusher will not be able to flush to disk which will result in memory pressure. Refer to Configuring the Columnstore to Work Effectively for more information.
`enable_background_merger`
`enable_background_statistics_collection`
`enable_binary_protocol`
`enable_blob_cache_sync_thread`
`enable_bottomless`
`enable_broadcast_left_join`
`enable_distributed_tracing`
`enable_histogram_to_unwrap_literals`
`enable_ir_cache`
`enable_local_shuffle_group_by`
`enable_multipartition_queries`
`enable_resource_pool_security`
`enable_sites`
`enable_skiplist_sampling_for_selectivity`
`enable_sort_on_load`
`end_tags_on_all_databases`
`error_count`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`estimate_zero_rows_when_sampling_data_is_missing`
`exclude_scalar_subselects_from_filters`
`experimental_csi_join_threshold`
`experimental_disable_multipartition_parallel_read`
`expire_root_password`
`explain_joinplan_costs`
`exporter_password`
exporter_path	This variable is deprecated and non-operational.
`exporter_ssl_key_passphrase`
`external_auth_tracing_time_limit`
`external_functions_whitelist`
`external_user`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`failover_initial_grace_interval_seconds`
`failover_maximum_grace_interval_seconds`
`force_bloom_filters`
`force_bushy_joins`
`force_heuristic_rewrites`
`force_table_pushdown`
`foreign_key_checks`
`forward_aggregator_plan_hash`
`general_log_file`
`geo_query_info`
`group_concat_max_len`
`hash_groupby_segment_distinct_values_threshold`
`have_openssl`
`have_query_cache`
`have_ssl`
`heartbeat_max_connection_saturation_timeout_ms`
`heartbeat_minimum_query_per_sec`
`heartbeat_period_ms`
`heartbeat_ping_failure_timeout_s`
`heartbeats_failed_before_node_failure`
`heartbeats_failed_before_reconnect`
`http_api_close_connection_on_user_drop`
`idle_thread_lifetime_seconds`
`ignore_builtin_innodb`
`ignore_insert_into_computed_column`
`init_connect`
`init_memsql_db_only`
`inlist_precision_limit`
`innodb_buffer_pool_size`
`innodb_strict_mode`
`insecure_accept_any_password_for_all_users`
`interactive_timeout`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`internal_allow_leaf_alters`
`internal_allow_systable_queries`
`internal_autostats_refresh_enabled`
`internal_cluster_replication_provision_timeout_retries`
`internal_columnstore_idle_flush_wait_seconds`
`internal_columnstore_ingest_aggressive_throttle_ms`
`internal_columnstore_max_uncompressed_blob_size`
`internal_columnstore_max_uncompressed_rowindex_blob_size`
`internal_columnstore_validate_blob_after_write`
`internal_columnstore_validate_blob_before_read`
`internal_columnstore_window_minimum_blob_size`
`internal_drop_all_from_plancache_legacy_behavior`
`internal_dump_bitcode_file`
`internal_dump_clean_bitcode_file`
`internal_dump_raw_bitcode_file`
`internal_enable_parallel_query_throttling`
`internal_extra_sync_replication_logging`
`internal_info_schema_show_hidden_tables`
`internal_keepalive_count`
`internal_keepalive_timeout`
`internal_llvm_compile_externally`
`internal_llvm_detect_cpu_features`
`internal_master_flush`
`internal_max_cte_depth`
`internal_minimum_local_size_for_llvm_lifetimes`
`internal_send_prehandshake_packet`
`internal_session_tracelogs_limit`
`internal_set_keepalive_on_connections`
`internal_set_user_timeout_on_connections`
`internal_slave_flush`
`internal_specialize_common_opcodes`
`internal_trace_compile_args`
`interp_first_auto_gen_helper`
`interpreter_mode_sampling_threshold`
`join_buffer_size`
`json_agg_max_len`
`lc_messages`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`lc_time_names`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`leaf_pushdown_default`
`leaf_pushdown_enable_rowcount`
`license`
`license_visibility`
`llvm_diagnostic_info`
`local_file_system_access_restricted`
`local_infile`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`lock_logging_min_latency`
`lock_upgrade`
`locked_in_memory`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`log_error`
`log_error_verbosity`
`log_output`
`log_queries_not_using_indexes`
`log_warnings`
`lower_case_table_names`
`materialize_ctes`
`max_broadcast_tree_rowcount`
`max_complex_type_elim_rowcount`
`max_connect_errors`
`max_error_count`
`max_heap_table_size`
`max_join_size`
`max_length_for_sort_data`
`max_recursive_cte_iterations`
`max_seeks_for_key`
`max_sort_length`
`max_subselect_aggregator_rowcount`
`max_user_connections`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`max_xact_cache_size_aggs`
`max_xact_cache_size_leaves`
`mbcc_phase_times`
`memsql_custom_build`
`memsql_license`
`minimum_core_count`
`minimum_memory_mb`
`ml_model`
`multi_range_count`
`multistatement_transactions`	This variable is deprecated and its value is ignored started in version 8.5.
`net_retry_count`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`num_workers_background_tasks_pool`
`old`
`old_local_join_optimizer`
`old_passwords`
`openssl_version`
`optimize_constants`
`optimize_expressions_larger_than`
`optimize_huge_expressions`
`optimize_mpl_before_printing`
`optimize_scopes`
`optimize_stmt_threshold`
`optimizer_beam_width`
`optimizer_cross_join_cost`
`optimizer_disable_operator_tree_nullability_check`
`optimizer_disable_right_join`
`optimizer_disable_semi_join_reduction`
`optimizer_disable_subselect_to_join`
`optimizer_empty_tables_limit`
`optimizer_enable_json_text_matching`
`optimizer_gb_placement_table_limit`
`optimizer_hash_join_cost`
`optimizer_latest`
`optimizer_merge_join_cost`
`optimizer_nested_join_cost`
`optimizer_num_partitions`
`optimizer_prune_level`
`optimizer_search_depth`
`optimizer_switch`
`optimizer_warnings`
`password_expiration_seconds`
`password_expiration_mode`
`password_history_count`
`pipelines_extractor_get_offsets_timeout_ms`
`pipelines_extractor_idle_timeout_ms`
`plancachedir`
`port_open_timeout`
`pre_handshake_packet_wait_period_ms`
`preload_buffer_size`
`preserve_original_colstore_json`
`profile_for_debug`
`proxy_user`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`quadratic_rewrite_size_limit`
`query_alloc_block_size`
`query_cache_size`
`query_cache_type`
`query_prealloc_size`
`query_rewrite_loop_iterations`
`read_buffer_size`
`read_only`
`recovery_batch_size`
`ref_repl_mgmt_threads`
`repartition_minimum_buffer_size`
`repl_mgmt_threads`
`replication_sync`	This variable has been deprecated and is no longer operational in SingleStore.
`replication_timeout_ms`
`report_mpl_optimizations`
`reported_hostname`
`reshuffle_group_by_base_cost`
`rewrite_verbose`
`row_lock_conflict_forces_implicit_rollback`
`rows_per_period`
`sampling_estimates_for_complex_filters`
`secure_auth`
`secure_mode`
`selectivity_estimation_min_sample_size`
`session_lock`
`set_global_variables_allowed_list`
`singlebox_optimizer_cost_based_threshold`
`skip_blob_crc_checks`
`skip_create_database_resource_check`
`skip_host_cache`
`skip_networking`
`skip_rebalance_blob_cache_warmup`
`skip_rebalance_resource_check`
`skip_show_database`
`slow_launch_time`
`sql_auto_is_null`
`sql_mode`
`sql_notes`
`sql_safe_updates`
`ssl_key_passphrase`
`statistics_warnings`
`strict_mode`
`strict_passwords`
`subquery_merge_with_outer_joins`
`sync2_timeout`
`sync_binlog`
`synchronize_bottomless_timeout_ms`
`synchronize_database_timeout`
`syslog_level`
`syslog_level_CONSENSUS`
`syslog_level_CSI`
`syslog_level_CS_QE`
`syslog_level_LOAD_DATA_INTERNAL_COMPRESSION`
`syslog_level_MCTE`
`syslog_level_METADATA`
`syslog_level_NETWORK`
`syslog_level_PARAMETRIZER`
`syslog_level_REPL`
`syslog_level_SEND_ERROR`
`syslog_level_SPARSE_COMPRESSION`
`syslog_level_TRANSACTIONS`
`syslog_level_WASM`
`syslog_location`
`syslog_protocol`
`target_replica_blob_cache_size_ratio`
`time_format`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`tmp_table_size`
`tmpdir`
`tracelog_level`
`tracelog_level_CONSENSUS`
`tracelog_level_CSI`
`tracelog_level_CS_QE`
`tracelog_level_LOAD_DATA_INTERNAL_COMPRESSION`
`tracelog_level_MCTE`
`tracelog_level_METADATA`
`tracelog_level_NETWORK`
`tracelog_level_PARAMETRIZER`
`tracelog_level_REPL`
`tracelog_level_SEND_ERROR`
`tracelog_level_SPARSE_COMPRESSION`
`tracelog_level_TRANSACTIONS`
`tracelog_level_WASM`
`tracelogsdir`
`track_leaked_memory`
`transaction_read_only`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`tx_read_only`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`udf_gc_expiry`
`udf_gc_interval`
`unique_checks`
`upgrade_skip_sync_repl_step`
`use_avx2`
`use_bind_address_for_outgoing`
`use_column_correlation`
`use_joincolumnstore`
`use_joincolumnstore_bailout`
`use_joincolumnstore_hash`
`use_joincolumnstore_trace`
`use_memfd_create`
`use_popcnt_instruction`
`use_seekable_json`
`v3_license_path`
`verify_column_compression`
`verify_fields_in_transitivity`
`version`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore. To check the version of SingleStore you are running, use the `memsql_version` variable instead.
`version_comment`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`wait_die_queue_max_length`
`wait_die_retry_until_timeout_on_die`
`wait_timeout`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.
`warning_count`	This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore.

Reserved Engine Variables

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