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System Variable Reference

This page lists all TiDB system variables and the documents that reference them in the documentation. You can view System Variables for more details of each variable.

Variable reference

allow_auto_random_explicit_insert

Referenced in:

authentication_ldap_sasl_auth_method_name

Referenced in:

authentication_ldap_sasl_bind_base_dn

Referenced in:

authentication_ldap_sasl_bind_root_dn

Referenced in:

authentication_ldap_sasl_bind_root_pwd

Referenced in:

authentication_ldap_sasl_ca_path

Referenced in:

authentication_ldap_sasl_init_pool_size

Referenced in:

authentication_ldap_sasl_max_pool_size

Referenced in:

authentication_ldap_sasl_server_host

Referenced in:

authentication_ldap_sasl_server_port

Referenced in:

authentication_ldap_sasl_tls

Referenced in:

authentication_ldap_simple_auth_method_name

Referenced in:

authentication_ldap_simple_bind_base_dn

Referenced in:

authentication_ldap_simple_bind_root_dn

Referenced in:

authentication_ldap_simple_bind_root_pwd

Referenced in:

authentication_ldap_simple_ca_path

Referenced in:

authentication_ldap_simple_init_pool_size

Referenced in:

authentication_ldap_simple_max_pool_size

Referenced in:

authentication_ldap_simple_server_host

Referenced in:

authentication_ldap_simple_server_port

Referenced in:

authentication_ldap_simple_tls

Referenced in:

auto_increment_increment

Referenced in:

auto_increment_offset

Referenced in:

autocommit

Referenced in:

block_encryption_mode

Referenced in:

character_set_client

Referenced in:

character_set_connection

Referenced in:

character_set_database

Referenced in:

character_set_results

Referenced in:

character_set_server

Referenced in:

collation_connection

Referenced in:

collation_database

Referenced in:

collation_server

Referenced in:

cte_max_recursion_depth

Referenced in:

datadir

Referenced in:

ddl_slow_threshold

Referenced in:

default_authentication_plugin

Referenced in:

default_collation_for_utf8mb4

Referenced in:

default_password_lifetime

Referenced in:

default_week_format

Referenced in:

disconnect_on_expired_password

Referenced in:

div_precision_increment

Referenced in:

error_count

Referenced in:

foreign_key_checks

Referenced in:

group_concat_max_len

Referenced in:

have_openssl

Referenced in:

have_ssl

Referenced in:

hostname

Referenced in:

identity

Referenced in:

init_connect

Referenced in:

innodb_lock_wait_timeout

Referenced in:

interactive_timeout

Referenced in:

last_insert_id

Referenced in:

last_plan_from_binding

Referenced in:

last_plan_from_cache

Referenced in:

last_sql_use_alloc

Referenced in:

license

Referenced in:

max_allowed_packet

Referenced in:

max_connections

Referenced in:

max_execution_time

Referenced in:

max_prepared_stmt_count

Referenced in:

mpp_exchange_compression_mode

Referenced in:

mpp_version

Referenced in:

password_history

Referenced in:

password_reuse_interval

Referenced in:

pd_enable_follower_handle_region

Referenced in:

plugin_dir

Referenced in:

plugin_load

Referenced in:

port

Referenced in:

rand_seed1

Referenced in:

rand_seed2

Referenced in:

require_secure_transport

Referenced in:

skip_name_resolve

Referenced in:

socket

Referenced in:

sql_mode

Referenced in:

sql_require_primary_key

Referenced in:

sql_select_limit

Referenced in:

ssl_ca

Referenced in:

ssl_cert

Referenced in:

ssl_key

Referenced in:

system_time_zone

Referenced in:

tidb_adaptive_closest_read_threshold

Referenced in:

tidb_allow_batch_cop

Referenced in:

tidb_allow_fallback_to_tikv

Referenced in:

tidb_allow_function_for_expression_index

Referenced in:

tidb_allow_mpp

Referenced in:

tidb_allow_remove_auto_inc

Referenced in:

tidb_allow_tiflash_cop

Referenced in:

tidb_analyze_column_options

Referenced in:

tidb_analyze_distsql_scan_concurrency

Referenced in:

tidb_analyze_partition_concurrency

Referenced in:

tidb_analyze_skip_column_types

Referenced in:

tidb_analyze_version

Referenced in:

tidb_auto_analyze_concurrency

Referenced in:

tidb_auto_analyze_end_time

Referenced in:

tidb_auto_analyze_partition_batch_size

Referenced in:

tidb_auto_analyze_ratio

Referenced in:

tidb_auto_analyze_start_time

Referenced in:

tidb_auto_build_stats_concurrency

Referenced in:

tidb_backoff_lock_fast

Referenced in:

tidb_backoff_weight

Referenced in:

tidb_batch_commit

Referenced in:

tidb_batch_delete

Referenced in:

tidb_batch_insert

Referenced in:

tidb_batch_pending_tiflash_count

Referenced in:

tidb_broadcast_join_threshold_count

Referenced in:

tidb_broadcast_join_threshold_size

Referenced in:

tidb_build_sampling_stats_concurrency

Referenced in:

tidb_build_stats_concurrency

Referenced in:

tidb_capture_plan_baselines

Referenced in:

tidb_cdc_write_source

Referenced in:

tidb_check_mb4_value_in_utf8

Referenced in:

tidb_checksum_table_concurrency

Referenced in:

tidb_cloud_storage_uri

Referenced in:

tidb_committer_concurrency

Referenced in:

tidb_config

Referenced in:

tidb_constraint_check_in_place

Referenced in:

tidb_constraint_check_in_place_pessimistic

Referenced in:

tidb_cost_model_version

Referenced in:

tidb_current_ts

Referenced in:

tidb_ddl_disk_quota

Referenced in:

tidb_ddl_enable_fast_reorg

Referenced in:

tidb_ddl_error_count_limit

Referenced in:

tidb_ddl_flashback_concurrency

Referenced in:

tidb_ddl_reorg_batch_size

Referenced in:

tidb_ddl_reorg_max_write_speed

Referenced in:

tidb_ddl_reorg_priority

Referenced in:

tidb_ddl_reorg_worker_cnt

Referenced in:

tidb_default_string_match_selectivity

Referenced in:

tidb_disable_txn_auto_retry

Referenced in:

tidb_distsql_scan_concurrency

Referenced in:

tidb_dml_batch_size

Referenced in:

tidb_dml_type

Referenced in:

tidb_enable_1pc

Referenced in:

tidb_enable_analyze_snapshot

Referenced in:

tidb_enable_async_commit

Referenced in:

tidb_enable_async_merge_global_stats

Referenced in:

tidb_enable_auto_analyze

Referenced in:

tidb_enable_auto_analyze_priority_queue

Referenced in:

tidb_enable_auto_increment_in_generated

Referenced in:

tidb_enable_batch_dml

Referenced in:

tidb_enable_cascades_planner

Referenced in:

tidb_enable_check_constraint

Referenced in:

tidb_enable_chunk_rpc

Referenced in:

tidb_enable_clustered_index

Referenced in:

tidb_enable_collect_execution_info

Referenced in:

tidb_enable_column_tracking

Referenced in:

tidb_enable_ddl

Referenced in:

tidb_enable_dist_task

Referenced in:

tidb_enable_enhanced_security

Referenced in:

tidb_enable_exchange_partition

Referenced in:

tidb_enable_extended_stats

Referenced in:

tidb_enable_external_ts_read

Referenced in:

tidb_enable_fast_analyze

Referenced in:

tidb_enable_fast_create_table

Referenced in:

tidb_enable_fast_table_check

Referenced in:

tidb_enable_foreign_key

Referenced in:

tidb_enable_gc_aware_memory_track

Referenced in:

tidb_enable_global_index

Referenced in:

tidb_enable_gogc_tuner

Referenced in:

tidb_enable_historical_stats

Referenced in:

tidb_enable_historical_stats_for_capture

Referenced in:

tidb_enable_index_merge

Referenced in:

tidb_enable_index_merge_join

Referenced in:

tidb_enable_inl_join_inner_multi_pattern

Referenced in:

tidb_enable_instance_plan_cache

Referenced in:

tidb_enable_lazy_cursor_fetch

Referenced in:

tidb_enable_legacy_instance_scope

Referenced in:

tidb_enable_list_partition

Referenced in:

tidb_enable_local_txn

Referenced in:

tidb_enable_metadata_lock

Referenced in:

tidb_enable_mutation_checker

Referenced in:

tidb_enable_new_cost_interface

Referenced in:

tidb_enable_new_only_full_group_by_check

Referenced in:

tidb_enable_non_prepared_plan_cache

Referenced in:

tidb_enable_non_prepared_plan_cache_for_dml

Referenced in:

tidb_enable_noop_functions

Referenced in:

tidb_enable_noop_variables

Referenced in:

tidb_enable_null_aware_anti_join

Referenced in:

tidb_enable_ordered_result_mode

Referenced in:

tidb_enable_outer_join_reorder

Referenced in:

tidb_enable_paging

Referenced in:

tidb_enable_parallel_apply

Referenced in:

tidb_enable_parallel_hashagg_spill

Referenced in:

tidb_enable_pipelined_window_function

Referenced in:

tidb_enable_plan_cache_for_param_limit

Referenced in:

tidb_enable_plan_cache_for_subquery

Referenced in:

tidb_enable_plan_replayer_capture

Referenced in:

tidb_enable_plan_replayer_continuous_capture

Referenced in:

tidb_enable_prepared_plan_cache

Referenced in:

tidb_enable_prepared_plan_cache_memory_monitor

Referenced in:

tidb_enable_pseudo_for_outdated_stats

Referenced in:

tidb_enable_rate_limit_action

Referenced in:

tidb_enable_resource_control

Referenced in:

tidb_enable_reuse_chunk

Referenced in:

tidb_enable_row_level_checksum

Referenced in:

tidb_enable_shared_lock_promotion

Referenced in:

tidb_enable_slow_log

Referenced in:

tidb_enable_stats_owner

Referenced in:

tidb_enable_stmt_summary

Referenced in:

tidb_enable_strict_double_type_check

Referenced in:

tidb_enable_table_partition

Referenced in:

tidb_enable_telemetry

Referenced in:

tidb_enable_tiflash_read_for_write_stmt

Referenced in:

tidb_enable_tmp_storage_on_oom

Referenced in:

tidb_enable_top_sql

Referenced in:

tidb_enable_tso_follower_proxy

Referenced in:

tidb_enable_unsafe_substitute

Referenced in:

tidb_enable_vectorized_expression

Referenced in:

tidb_enable_window_function

Referenced in:

tidb_enforce_mpp

Referenced in:

tidb_evolve_plan_baselines

Referenced in:

tidb_evolve_plan_task_end_time

Referenced in:

tidb_evolve_plan_task_max_time

Referenced in:

tidb_evolve_plan_task_start_time

Referenced in:

tidb_executor_concurrency

Referenced in:

tidb_expensive_query_time_threshold

Referenced in:

tidb_expensive_txn_time_threshold

Referenced in:

tidb_external_ts

Referenced in:

tidb_force_priority

Referenced in:

tidb_gc_concurrency

Referenced in:

tidb_gc_enable

Referenced in:

tidb_gc_life_time

Referenced in:

tidb_gc_max_wait_time

Referenced in:

tidb_gc_run_interval

Referenced in:

tidb_gc_scan_lock_mode

Referenced in:

tidb_general_log

Referenced in:

tidb_generate_binary_plan

Referenced in:

tidb_gogc_tuner_max_value

Referenced in:

tidb_gogc_tuner_min_value

Referenced in:

tidb_gogc_tuner_threshold

Referenced in:

tidb_guarantee_linearizability

Referenced in:

tidb_hash_exchange_with_new_collation

Referenced in:

tidb_hash_join_concurrency

Referenced in:

tidb_hash_join_version

Referenced in:

tidb_hashagg_final_concurrency

Referenced in:

tidb_hashagg_partial_concurrency

Referenced in:

tidb_historical_stats_duration

Referenced in:

tidb_idle_transaction_timeout

Referenced in:

tidb_ignore_prepared_cache_close_stmt

Referenced in:

tidb_index_join_batch_size

Referenced in:

tidb_index_join_double_read_penalty_cost_rate

Referenced in:

tidb_index_lookup_concurrency

Referenced in:

tidb_index_lookup_join_concurrency

Referenced in:

tidb_index_lookup_size

Referenced in:

tidb_index_merge_intersection_concurrency

Referenced in:

tidb_index_serial_scan_concurrency

Referenced in:

tidb_init_chunk_size

Referenced in:

tidb_instance_plan_cache_max_size

Referenced in:

tidb_instance_plan_cache_reserved_percentage

Referenced in:

tidb_isolation_read_engines

Referenced in:

tidb_last_ddl_info

Referenced in:

tidb_last_plan_replayer_token

Referenced in:

tidb_last_query_info

Referenced in:

tidb_last_txn_info

Referenced in:

tidb_load_based_replica_read_threshold

Referenced in:

tidb_load_binding_timeout

Referenced in:

tidb_lock_unchanged_keys

Referenced in:

tidb_log_file_max_days

Referenced in:

tidb_low_resolution_tso

Referenced in:

tidb_low_resolution_tso_update_interval

Referenced in:

tidb_max_auto_analyze_time

Referenced in:

tidb_max_bytes_before_tiflash_external_group_by

Referenced in:

tidb_max_bytes_before_tiflash_external_join

Referenced in:

tidb_max_bytes_before_tiflash_external_sort

Referenced in:

tidb_max_chunk_size

Referenced in:

tidb_max_delta_schema_count

Referenced in:

tidb_max_paging_size

Referenced in:

tidb_max_tiflash_threads

Referenced in:

tidb_mem_oom_action

Referenced in:

tidb_mem_quota_analyze

Referenced in:

tidb_mem_quota_apply_cache

Referenced in:

tidb_mem_quota_binding_cache

Referenced in:

tidb_mem_quota_query

Referenced in:

tidb_memory_debug_mode_alarm_ratio

Referenced in:

tidb_memory_debug_mode_min_heap_inuse

Referenced in:

tidb_memory_usage_alarm_keep_record_num

Referenced in:

tidb_memory_usage_alarm_ratio

Referenced in:

tidb_merge_join_concurrency

Referenced in:

tidb_merge_partition_stats_concurrency

Referenced in:

tidb_metric_query_range_duration

Referenced in:

tidb_metric_query_step

Referenced in:

tidb_min_paging_size

Referenced in:

tidb_mpp_store_fail_ttl

Referenced in:

tidb_multi_statement_mode

Referenced in:

tidb_non_prepared_plan_cache_size

Referenced in:

tidb_nontransactional_ignore_error

Referenced in:

tidb_opt_advanced_join_hint

Referenced in:

tidb_opt_agg_push_down

Referenced in:

tidb_opt_broadcast_cartesian_join

Referenced in:

tidb_opt_concurrency_factor

Referenced in:

tidb_opt_copcpu_factor

Referenced in:

tidb_opt_correlation_exp_factor

Referenced in:

tidb_opt_correlation_threshold

Referenced in:

tidb_opt_cpu_factor

Referenced in:

tidb_opt_derive_topn

Referenced in:

tidb_opt_desc_factor

Referenced in:

tidb_opt_disk_factor

Referenced in:

tidb_opt_distinct_agg_push_down

Referenced in:

tidb_opt_enable_correlation_adjustment

Referenced in:

tidb_opt_enable_fuzzy_binding

Referenced in:

tidb_opt_enable_hash_join

Referenced in:

tidb_opt_enable_late_materialization

Referenced in:

tidb_opt_enable_mpp_shared_cte_execution

Referenced in:

tidb_opt_enable_non_eval_scalar_subquery

Referenced in:

tidb_opt_fix_control

Referenced in:

tidb_opt_force_inline_cte

Referenced in:

tidb_opt_insubq_to_join_and_agg

Referenced in:

tidb_opt_join_reorder_threshold

Referenced in:

tidb_opt_limit_push_down_threshold

Referenced in:

tidb_opt_memory_factor

Referenced in:

tidb_opt_mpp_outer_join_fixed_build_side

Referenced in:

tidb_opt_network_factor

Referenced in:

tidb_opt_objective

Referenced in:

tidb_opt_ordering_index_selectivity_ratio

Referenced in:

tidb_opt_ordering_index_selectivity_threshold

Referenced in:

tidb_opt_prefer_range_scan

Referenced in:

tidb_opt_prefix_index_single_scan

Referenced in:

tidb_opt_projection_push_down

Referenced in:

tidb_opt_range_max_size

Referenced in:

tidb_opt_scan_factor

Referenced in:

tidb_opt_seek_factor

Referenced in:

tidb_opt_skew_distinct_agg

Referenced in:

tidb_opt_three_stage_distinct_agg

Referenced in:

tidb_opt_tiflash_concurrency_factor

Referenced in:

tidb_opt_use_invisible_indexes

Referenced in:

tidb_opt_write_row_id

Referenced in:

tidb_optimizer_selectivity_level

Referenced in:

tidb_partition_prune_mode

Referenced in:

tidb_persist_analyze_options

Referenced in:

tidb_pessimistic_txn_fair_locking

Referenced in:

tidb_placement_mode

Referenced in:

tidb_plan_cache_invalidation_on_fresh_stats

Referenced in:

tidb_plan_cache_max_plan_size

Referenced in:

tidb_pprof_sql_cpu

Referenced in:

tidb_pre_split_regions

Referenced in:

tidb_prefer_broadcast_join_by_exchange_data_size

Referenced in:

tidb_prepared_plan_cache_memory_guard_ratio

Referenced in:

tidb_prepared_plan_cache_size

Referenced in:

tidb_projection_concurrency

Referenced in:

tidb_query_log_max_len

Referenced in:

tidb_rc_read_check_ts

Referenced in:

tidb_rc_write_check_ts

Referenced in:

tidb_read_consistency

Referenced in:

tidb_read_staleness

Referenced in:

tidb_record_plan_in_slow_log

Referenced in:

tidb_redact_log

Referenced in:

tidb_regard_null_as_point

Referenced in:

tidb_remove_orderby_in_subquery

Referenced in:

tidb_replica_read

Referenced in:

tidb_request_source_type

Referenced in:

tidb_resource_control_strict_mode

Referenced in:

tidb_restricted_read_only

Referenced in:

tidb_retry_limit

Referenced in:

tidb_row_format_version

Referenced in:

tidb_runtime_filter_mode

Referenced in:

tidb_runtime_filter_type

Referenced in:

tidb_scatter_region

Referenced in:

tidb_schema_cache_size

Referenced in:

tidb_schema_version_cache_limit

Referenced in:

tidb_server_memory_limit

Referenced in:

tidb_server_memory_limit_gc_trigger

Referenced in:

tidb_server_memory_limit_sess_min_size

Referenced in:

tidb_service_scope

Referenced in:

tidb_session_alias

Referenced in:

tidb_session_plan_cache_size

Referenced in:

tidb_shard_allocate_step

Referenced in:

tidb_shard_row_id_bits

Referenced in:

tidb_simplified_metrics

Referenced in:

tidb_skip_ascii_check

Referenced in:

tidb_skip_isolation_level_check

Referenced in:

tidb_skip_missing_partition_stats

Referenced in:

tidb_skip_utf8_check

Referenced in:

tidb_slow_log_threshold

Referenced in:

tidb_slow_query_file

Referenced in:

tidb_snapshot

Referenced in:

tidb_source_id

Referenced in:

tidb_stats_cache_mem_quota

Referenced in:

tidb_stats_load_pseudo_timeout

Referenced in:

tidb_stats_load_sync_wait

Referenced in:

tidb_stmt_summary_enable_persistent

Referenced in:

tidb_stmt_summary_file_max_backups

Referenced in:

tidb_stmt_summary_file_max_days

Referenced in:

tidb_stmt_summary_file_max_size

Referenced in:

tidb_stmt_summary_filename

Referenced in:

tidb_stmt_summary_history_size

Referenced in:

tidb_stmt_summary_internal_query

Referenced in:

tidb_stmt_summary_max_sql_length

Referenced in:

tidb_stmt_summary_max_stmt_count

Referenced in:

tidb_stmt_summary_refresh_interval

Referenced in:

tidb_store_batch_size

Referenced in:

tidb_store_limit

Referenced in:

tidb_streamagg_concurrency

Referenced in:

tidb_super_read_only

Referenced in:

tidb_sysdate_is_now

Referenced in:

tidb_sysproc_scan_concurrency

Referenced in:

tidb_table_cache_lease

Referenced in:

tidb_tmp_table_max_size

Referenced in:

tidb_top_sql_max_meta_count

Referenced in:

tidb_top_sql_max_time_series_count

Referenced in:

tidb_track_aggregate_memory_usage

Referenced in:

tidb_tso_client_batch_max_wait_time

Referenced in:

tidb_tso_client_rpc_mode

Referenced in:

tidb_ttl_delete_batch_size

Referenced in:

tidb_ttl_delete_rate_limit

Referenced in:

tidb_ttl_delete_worker_count

Referenced in:

tidb_ttl_job_enable

Referenced in:

tidb_ttl_job_schedule_window_end_time

Referenced in:

tidb_ttl_job_schedule_window_start_time

Referenced in:

tidb_ttl_running_tasks

Referenced in:

tidb_ttl_scan_batch_size

Referenced in:

tidb_ttl_scan_worker_count

Referenced in:

tidb_txn_assertion_level

Referenced in:

tidb_txn_commit_batch_size

Referenced in:

tidb_txn_entry_size_limit

Referenced in:

tidb_txn_mode

Referenced in:

tidb_use_plan_baselines

Referenced in:

tidb_wait_split_region_finish

Referenced in:

tidb_wait_split_region_timeout

Referenced in:

tidb_window_concurrency

Referenced in:

tiflash_fastscan

Referenced in:

tiflash_fine_grained_shuffle_batch_size

Referenced in:

tiflash_fine_grained_shuffle_stream_count

Referenced in:

tiflash_hashagg_preaggregation_mode

Referenced in:

tiflash_mem_quota_query_per_node

Referenced in:

tiflash_query_spill_ratio

Referenced in:

tiflash_replica_read

Referenced in:

tikv_client_read_timeout

Referenced in:

time_zone

Referenced in:

timestamp

Referenced in:

transaction_isolation

Referenced in:

tx_isolation

Referenced in:

tx_isolation_one_shot

Referenced in:

tx_read_ts

Referenced in:

txn_scope

Referenced in:

validate_password.check_user_name

Referenced in:

validate_password.dictionary

Referenced in:

validate_password.enable

Referenced in:

validate_password.length

Referenced in:

validate_password.mixed_case_count

Referenced in:

validate_password.number_count

Referenced in:

validate_password.policy

Referenced in:

validate_password.special_char_count

Referenced in:

version

Referenced in:

version_comment

Referenced in:

version_compile_machine

Referenced in:

version_compile_os

Referenced in:

wait_timeout

Referenced in:

warning_count

Referenced in:

windowing_use_high_precision

Referenced in:

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