From 74817600f5859c146f3f78f298ec8e603e3dd311 Mon Sep 17 00:00:00 2001 From: doc-claw-bot Date: Wed, 1 Jul 2026 01:37:05 +0000 Subject: [PATCH 1/4] docs: refresh SHOW VARIABLES example output --- .../sql-statement-show-variables.md | 131 +++--------------- 1 file changed, 20 insertions(+), 111 deletions(-) diff --git a/sql-statements/sql-statement-show-variables.md b/sql-statements/sql-statement-show-variables.md index ae9897276d469..c47d929408633 100644 --- a/sql-statements/sql-statement-show-variables.md +++ b/sql-statements/sql-statement-show-variables.md @@ -20,120 +20,29 @@ ShowLikeOrWhere ::= ## Examples -List all TiDB specific variables. For detailed description, refer to [System Variables](/system-variables.md). +The following example shows part of the TiDB-specific global variables. For detailed descriptions, refer to [System Variables](/system-variables.md). ```sql mysql> SHOW GLOBAL VARIABLES LIKE 'tidb%'; -+-------------------------------------+---------------------+ -| Variable_name | Value | -+-------------------------------------+---------------------+ -| tidb_allow_batch_cop | 0 | -| tidb_allow_remove_auto_inc | 0 | -| tidb_auto_analyze_end_time | 23:59 +0000 | -| tidb_auto_analyze_ratio | 0.5 | -| tidb_auto_analyze_start_time | 00:00 +0000 | -| tidb_backoff_lock_fast | 100 | -| tidb_backoff_weight | 2 | -| tidb_batch_commit | 0 | -| tidb_batch_delete | 0 | -| tidb_build_stats_concurrency | 4 | -| tidb_capture_plan_baselines | off | -| tidb_check_mb4_value_in_utf8 | 1 | -| tidb_checksum_table_concurrency | 4 | -| tidb_config | | -| tidb_constraint_check_in_place | 0 | -| tidb_current_ts | 0 | -| tidb_ddl_error_count_limit | 512 | -| tidb_ddl_reorg_batch_size | 256 | -| tidb_ddl_reorg_priority | PRIORITY_LOW | -| tidb_ddl_reorg_worker_cnt | 4 | -| tidb_disable_txn_auto_retry | 1 | -| tidb_distsql_scan_concurrency | 15 | -| tidb_dml_batch_size | 20000 | -| tidb_enable_cascades_planner | 0 | -| tidb_enable_chunk_rpc | 1 | -| tidb_enable_collect_execution_info | 1 | -| tidb_enable_index_merge | 0 | -| tidb_enable_noop_functions | 0 | -| tidb_enable_radix_join | 0 | -| tidb_enable_slow_log | 1 | -| tidb_enable_stmt_summary | 1 | -| tidb_enable_table_partition | on | -| tidb_enable_vectorized_expression | 1 | -| tidb_enable_window_function | 1 | -| tidb_evolve_plan_baselines | off | -| tidb_evolve_plan_task_end_time | 23:59 +0000 | -| tidb_evolve_plan_task_max_time | 600 | -| tidb_evolve_plan_task_start_time | 00:00 +0000 | -| tidb_expensive_query_time_threshold | 60 | -| tidb_force_priority | NO_PRIORITY | -| tidb_general_log | 0 | -| tidb_hash_join_concurrency | 5 | -| tidb_hashagg_final_concurrency | 4 | -| tidb_hashagg_partial_concurrency | 4 | -| tidb_index_join_batch_size | 25000 | -| tidb_index_lookup_concurrency | 4 | -| tidb_index_lookup_join_concurrency | 4 | -| tidb_index_lookup_size | 20000 | -| tidb_index_serial_scan_concurrency | 1 | -| tidb_init_chunk_size | 32 | -| tidb_isolation_read_engines | tikv, tiflash, tidb | -| tidb_low_resolution_tso | 0 | -| tidb_max_chunk_size | 1024 | -| tidb_max_delta_schema_count | 1024 | -| tidb_mem_quota_hashjoin | 34359738368 | -| tidb_mem_quota_indexlookupjoin | 34359738368 | -| tidb_mem_quota_indexlookupreader | 34359738368 | -| tidb_mem_quota_mergejoin | 34359738368 | -| tidb_mem_quota_nestedloopapply | 34359738368 | -| tidb_mem_quota_query | 1073741824 | -| tidb_mem_quota_sort | 34359738368 | -| tidb_mem_quota_topn | 34359738368 | -| tidb_metric_query_range_duration | 60 | -| tidb_metric_query_step | 60 | -| tidb_opt_agg_push_down | 0 | -| tidb_opt_concurrency_factor | 3 | -| tidb_opt_copcpu_factor | 3 | -| tidb_opt_correlation_exp_factor | 1 | -| tidb_opt_correlation_threshold | 0.9 | -| tidb_opt_cpu_factor | 3 | -| tidb_opt_desc_factor | 3 | -| tidb_opt_disk_factor | 1.5 | -| tidb_opt_distinct_agg_push_down | 0 | -| tidb_opt_insubq_to_join_and_agg | 1 | -| tidb_opt_join_reorder_threshold | 0 | -| tidb_opt_memory_factor | 0.001 | -| tidb_opt_network_factor | 1 | -| tidb_opt_scan_factor | 1.5 | -| tidb_opt_seek_factor | 20 | -| tidb_opt_write_row_id | 0 | -| tidb_optimizer_selectivity_level | 0 | -| tidb_pprof_sql_cpu | 0 | -| tidb_projection_concurrency | 4 | -| tidb_query_log_max_len | 4096 | -| tidb_record_plan_in_slow_log | 1 | -| tidb_replica_read | leader | -| tidb_retry_limit | 10 | -| tidb_row_format_version | 2 | -| tidb_scatter_region | | -| tidb_skip_isolation_level_check | 0 | -| tidb_skip_utf8_check | 0 | -| tidb_slow_log_threshold | 300 | -| tidb_slow_query_file | tidb-slow.log | -| tidb_snapshot | | -| tidb_stmt_summary_history_size | 24 | -| tidb_stmt_summary_internal_query | 0 | -| tidb_stmt_summary_max_sql_length | 4096 | -| tidb_stmt_summary_max_stmt_count | 3000 | -| tidb_stmt_summary_refresh_interval | 1800 | -| tidb_store_limit | 0 | -| tidb_txn_mode | | -| tidb_use_plan_baselines | on | -| tidb_wait_split_region_finish | 1 | -| tidb_wait_split_region_timeout | 300 | -| tidb_window_concurrency | 4 | -+-------------------------------------+---------------------+ -108 rows in set (0.01 sec) ++--------------------------------------+-------------+ +| Variable_name | Value | ++--------------------------------------+-------------+ +| tidb_accelerate_user_creation_update | OFF | +| tidb_adaptive_closest_read_threshold | 4096 | +| tidb_advancer_check_point_lag_limit | 48h0m0s | +| tidb_allow_batch_cop | 1 | +| tidb_allow_fallback_to_tikv | | +| tidb_allow_mpp | ON | +| ... | ... | +| tidb_txn_commit_batch_size | 16384 | +| tidb_txn_entry_size_limit | 0 | +| tidb_txn_mode | pessimistic | +| tidb_use_plan_baselines | ON | +| tidb_wait_split_region_finish | ON | +| tidb_wait_split_region_timeout | 300 | +| tidb_window_concurrency | -1 | ++--------------------------------------+-------------+ +338 rows in set mysql> SHOW GLOBAL VARIABLES LIKE 'time_zone%'; +---------------+--------+ From 359a1aeb0d22f75309b9d08f015b3081180b3138 Mon Sep 17 00:00:00 2001 From: doc-claw-bot Date: Wed, 1 Jul 2026 03:20:34 +0000 Subject: [PATCH 2/4] docs: use a shorter SHOW VARIABLES example --- .../sql-statement-show-variables.md | 38 +++++++++---------- 1 file changed, 17 insertions(+), 21 deletions(-) diff --git a/sql-statements/sql-statement-show-variables.md b/sql-statements/sql-statement-show-variables.md index c47d929408633..966ddebef1fa1 100644 --- a/sql-statements/sql-statement-show-variables.md +++ b/sql-statements/sql-statement-show-variables.md @@ -20,29 +20,25 @@ ShowLikeOrWhere ::= ## Examples -The following example shows part of the TiDB-specific global variables. For detailed descriptions, refer to [System Variables](/system-variables.md). +The following example shows some TiDB statement summary global variables. For detailed descriptions, refer to [System Variables](/system-variables.md). ```sql -mysql> SHOW GLOBAL VARIABLES LIKE 'tidb%'; -+--------------------------------------+-------------+ -| Variable_name | Value | -+--------------------------------------+-------------+ -| tidb_accelerate_user_creation_update | OFF | -| tidb_adaptive_closest_read_threshold | 4096 | -| tidb_advancer_check_point_lag_limit | 48h0m0s | -| tidb_allow_batch_cop | 1 | -| tidb_allow_fallback_to_tikv | | -| tidb_allow_mpp | ON | -| ... | ... | -| tidb_txn_commit_batch_size | 16384 | -| tidb_txn_entry_size_limit | 0 | -| tidb_txn_mode | pessimistic | -| tidb_use_plan_baselines | ON | -| tidb_wait_split_region_finish | ON | -| tidb_wait_split_region_timeout | 300 | -| tidb_window_concurrency | -1 | -+--------------------------------------+-------------+ -338 rows in set +mysql> SHOW GLOBAL VARIABLES LIKE 'tidb_stmt_summary%'; ++-------------------------------------+---------------------+ +| Variable_name | Value | ++-------------------------------------+---------------------+ +| tidb_stmt_summary_enable_persistent | OFF | +| tidb_stmt_summary_file_max_backups | 0 | +| tidb_stmt_summary_file_max_days | 3 | +| tidb_stmt_summary_file_max_size | 64 | +| tidb_stmt_summary_filename | tidb-statements.log | +| tidb_stmt_summary_history_size | 24 | +| tidb_stmt_summary_internal_query | OFF | +| tidb_stmt_summary_max_sql_length | 4096 | +| tidb_stmt_summary_max_stmt_count | 3000 | +| tidb_stmt_summary_refresh_interval | 1800 | ++-------------------------------------+---------------------+ +10 rows in set (0.001 sec) mysql> SHOW GLOBAL VARIABLES LIKE 'time_zone%'; +---------------+--------+ From 6fe9e41f5034478b9d1656d662d269ec1dbc30aa Mon Sep 17 00:00:00 2001 From: Grace Cai Date: Wed, 1 Jul 2026 18:09:24 +0800 Subject: [PATCH 3/4] Update sql-statements/sql-statement-show-variables.md --- sql-statements/sql-statement-show-variables.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sql-statements/sql-statement-show-variables.md b/sql-statements/sql-statement-show-variables.md index 966ddebef1fa1..f67aa5957357a 100644 --- a/sql-statements/sql-statement-show-variables.md +++ b/sql-statements/sql-statement-show-variables.md @@ -20,7 +20,7 @@ ShowLikeOrWhere ::= ## Examples -The following example shows some TiDB statement summary global variables. For detailed descriptions, refer to [System Variables](/system-variables.md). +The following example demonstrates how to use the `SHOW [GLOBAL|SESSION] VARIABLES` statement to show variables whose names match a specific pattern. For detailed descriptions of these variables, see [System Variables](/system-variables.md). ```sql mysql> SHOW GLOBAL VARIABLES LIKE 'tidb_stmt_summary%'; From f5ec881ee4a671eede986c7a4cb7694be7436993 Mon Sep 17 00:00:00 2001 From: Grace Cai Date: Wed, 1 Jul 2026 18:11:33 +0800 Subject: [PATCH 4/4] Apply suggestions from code review --- sql-statements/sql-statement-show-variables.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sql-statements/sql-statement-show-variables.md b/sql-statements/sql-statement-show-variables.md index f67aa5957357a..400f07d227979 100644 --- a/sql-statements/sql-statement-show-variables.md +++ b/sql-statements/sql-statement-show-variables.md @@ -20,7 +20,7 @@ ShowLikeOrWhere ::= ## Examples -The following example demonstrates how to use the `SHOW [GLOBAL|SESSION] VARIABLES` statement to show variables whose names match a specific pattern. For detailed descriptions of these variables, see [System Variables](/system-variables.md). +The following example demonstrates how to use the `SHOW [GLOBAL|SESSION] VARIABLES` statement to show variables whose names or values match a specific pattern. For detailed descriptions of these variables, see [System Variables](/system-variables.md). ```sql mysql> SHOW GLOBAL VARIABLES LIKE 'tidb_stmt_summary%';