From 97020bcf807bd72a60a98da847ddf7782b6d18ee Mon Sep 17 00:00:00 2001
From: Dongyang Li <hello_stephen@qq.com>
Date: Wed, 9 Mar 2022 13:07:32 +0800
Subject: [PATCH] [doc] update substring.md (#8398)

correct a slip of pen.
---
 .../sql-reference/sql-functions/string-functions/substring.md   | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/zh-CN/sql-reference/sql-functions/string-functions/substring.md b/docs/zh-CN/sql-reference/sql-functions/string-functions/substring.md
index cdbbc2b056..c56bc989fa 100644
--- a/docs/zh-CN/sql-reference/sql-functions/string-functions/substring.md
+++ b/docs/zh-CN/sql-reference/sql-functions/string-functions/substring.md
@@ -40,7 +40,7 @@ under the License.
 ## example
 
 ```
-mysql> select substring('abc1', -2);
+mysql> select substring('abc1', 2);
 +-----------------------------+
 | substring('abc1', 2)        |
 +-----------------------------+