From 676a4581b18bed0a45e65728928161ff4df06ce7 Mon Sep 17 00:00:00 2001 From: TomShawn <41534398+TomShawn@users.noreply.github.com> Date: Thu, 18 Aug 2022 15:19:58 +0800 Subject: [PATCH] Apply suggestions from code review Co-authored-by: Aolin --- system-variables.md | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/system-variables.md b/system-variables.md index 7bbf959ce6a29..4c4a37a3a7ba7 100644 --- a/system-variables.md +++ b/system-variables.md @@ -347,7 +347,7 @@ This variable is an alias for `last_insert_id`. - If you set the variable to a value that exceeds the upper limit `1048576`, `1048576` is used instead: ```sql -mysql> SET GLOBAL max_prepared_stmt_count=1048577; +mysql> SET GLOBAL max_prepared_stmt_count = 1048577; Query OK, 0 rows affected, 1 warning (0.01 sec) mysql> SHOW WARNINGS; @@ -1773,7 +1773,7 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified - Range: `[0, 2]` - Indicates whether to allow the Broadcast Cartesian Join. - `0` means that the Broadcast Cartesian Join is not allowed. `1` means that it is allowed based on [`tidb_broadcast_join_threshold_count`](#tidb_broadcast_join_threshold_count-new-in-v50). `2` means that it is always allowed even if the table size exceeds the threshold. -- This variable is internally used in TiDB, and it is not recommended to modify its value. +- This variable is internally used in TiDB, and it is **NOT** recommended to modify its value. ### tidb_opt_concurrency_factor @@ -1782,7 +1782,7 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified - Type: Float - Range: `[0, 2147483647]` - Default value: `3.0` -- Indicates the CPU cost of starting a Golang goroutine in TiDB. This variable is internally used in the [Cost Model](/cost-model.md), and it is not recommended to modify its value. +- Indicates the CPU cost of starting a Golang goroutine in TiDB. This variable is internally used in the [Cost Model](/cost-model.md), and it is **NOT** recommended to modify its value. ### tidb_opt_cop_cpu_factor @@ -1791,7 +1791,7 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified - Type: Float - Range: `[0, 2147483647]` - Default value: `3.0` -- Indicates the CPU cost for TiKV Coprocessor to process one row. This variable is internally used in the [Cost Model](/cost-model.md), and it is not recommended to modify its value. +- Indicates the CPU cost for TiKV Coprocessor to process one row. This variable is internally used in the [Cost Model](/cost-model.md), and it is **NOT** recommended to modify its value. ### tidb_opt_correlation_exp_factor @@ -1822,7 +1822,7 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified - Type: Float - Range: `[0, 2147483647]` - Default value: `3.0` -- Indicates the CPU cost for TiDB to process one row. This variable is internally used in the [Cost Model](/cost-model.md), and it is not recommended to modify its value. +- Indicates the CPU cost for TiDB to process one row. This variable is internally used in the [Cost Model](/cost-model.md), and it is **NOT** recommended to modify its value. ### tidb_opt_desc_scan_factor @@ -1831,7 +1831,7 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified - Type: Float - Range: `[0, 2147483647]` - Default value: `3.0` -- Indicates the cost for TiKV to scan one row from the disk in descending order. This variable is internally used in the [Cost Model](/cost-model.md), and it is not recommended to modify its value. +- Indicates the cost for TiKV to scan one row from the disk in descending order. This variable is internally used in the [Cost Model](/cost-model.md), and it is **NOT** recommended to modify its value. ### tidb_opt_disk_factor @@ -1840,7 +1840,7 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified - Type: Float - Range: `[0, 2147483647]` - Default value: `1.5` -- Indicates the I/O cost for TiDB to read or write one byte of data from or to the temporary disk. This variable is internally used in the [Cost Model](/cost-model.md), and it is not recommended to modify its value. +- Indicates the I/O cost for TiDB to read or write one byte of data from or to the temporary disk. This variable is internally used in the [Cost Model](/cost-model.md), and it is **NOT** recommended to modify its value. ### tidb_opt_distinct_agg_push_down @@ -1928,7 +1928,7 @@ mysql> desc select count(distinct a) from test.t; - Type: Float - Range: `[0, 2147483647]` - Default value: `0.001` -- Indicates the memory cost for TiDB to store one row. This variable is internally used in the [Cost Model](/cost-model.md), and it is not recommended to modify its value. +- Indicates the memory cost for TiDB to store one row. This variable is internally used in the [Cost Model](/cost-model.md), and it is **NOT** recommended to modify its value. ### tidb_opt_mpp_outer_join_fixed_build_side New in v5.1.0 @@ -1945,7 +1945,7 @@ mysql> desc select count(distinct a) from test.t; - Type: Float - Range: `[0, 2147483647]` - Default value: `1.0` -- Indicates the net cost of transferring 1 byte of data through the network. This variable is internally used in the [Cost Model](/cost-model.md), and it is not recommended to modify its value. +- Indicates the net cost of transferring 1 byte of data through the network. This variable is internally used in the [Cost Model](/cost-model.md), and it is **NOT** recommended to modify its value. ### tidb_opt_prefer_range_scan New in v5.0 @@ -1995,7 +1995,7 @@ explain select * from t where age=5; - Type: Float - Range: `[0, 2147483647]` - Default value: `1.5` -- Indicates the cost for TiKV to scan one row of data from the disk in ascending order. This variable is internally used in the [Cost Model](/cost-model.md), and it is not recommended to modify its value. +- Indicates the cost for TiKV to scan one row of data from the disk in ascending order. This variable is internally used in the [Cost Model](/cost-model.md), and it is **NOT** recommended to modify its value. ### tidb_opt_seek_factor @@ -2004,7 +2004,7 @@ explain select * from t where age=5; - Type: Float - Range: `[0, 2147483647]` - Default value: `20` -- Indicates the start-up cost for TiDB to request data from TiKV. This variable is internally used in the [Cost Model](/cost-model.md), and it is not recommended to modify its value. +- Indicates the start-up cost for TiDB to request data from TiKV. This variable is internally used in the [Cost Model](/cost-model.md), and it is **NOT** recommended to modify its value. ### tidb_opt_skew_distinct_agg New in v6.2.0