From 44b609715dae45e5b388d2a5d3630af3d7862fbb Mon Sep 17 00:00:00 2001
From: JoyinQin <56883733+Joyinqin@users.noreply.github.com>
Date: Mon, 2 Nov 2020 14:00:33 +0800
Subject: [PATCH 1/2] Update sql-logical-optimization.md

---
 sql-logical-optimization.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sql-logical-optimization.md b/sql-logical-optimization.md
index 66b0d6a8e8613..bcb86ca646a4a 100644
--- a/sql-logical-optimization.md
+++ b/sql-logical-optimization.md
@@ -4,7 +4,7 @@ title: SQL Logical Optimization
 
 # SQL Logical Optimization
 
-This chapter explains some key logic rewrites to help you understand how TiDB generates the final query plan. For example, when you execute the `select * from t where t.a in (select * from t1 where t1.b=t.b)` query in TiDB, you will find that the `IN` sub-query `t.a in (select t1.a from t1 where t1.b=t.b` does not exist because TiDB has made some rewrites here.
+This chapter explains some key logic rewrites to help you understand how TiDB generates the final query plan. For example, when you execute the `select * from t where t.a in (select t1.a from t1 where t1.b=t.b)` query in TiDB, you will find that the `IN` sub-query `t.a in (select t1.a from t1 where t1.b=t.b)` does not exist because TiDB has made some rewrites here.
 
 This chapter introduces the following key rewrites:
 

From d36a4446ffaa8d263fd6c1296b2f20ead0edcff3 Mon Sep 17 00:00:00 2001
From: JoyinQin <56883733+Joyinqin@users.noreply.github.com>
Date: Mon, 2 Nov 2020 14:03:37 +0800
Subject: [PATCH 2/2] Update system-variables.md

---
 system-variables.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/system-variables.md b/system-variables.md
index 29e0fa7507286..3fe20d91d5228 100644
--- a/system-variables.md
+++ b/system-variables.md
@@ -688,7 +688,7 @@ set tidb_query_log_max_len = 20
 
 ### tidb_skip_isolation_level_check
 
-- Scope: SESSION
+- Scope: SESSION | GLOBAL
 - Default value: 0
 - After this switch is enabled, if an isolation level unsupported by TiDB is assigned to `tx_isolation`, no error is reported. This helps improve compatibility with applications that set (but do not depend on) a different isolation level.