commit e5e1d89c2d3e5c773696d0fc0af2b28036744a79
Author: root <root@poempeng1626087712045-0.poempeng1626087712045.default.svc.cluster.local>
Date:   Tue Sep 14 16:10:07 2021 +0800

    json_table wrong behaviour

diff --git a/sql/table_function.cc b/sql/table_function.cc
index 3af81dba53b..7106c72b69b 100644
--- a/sql/table_function.cc
+++ b/sql/table_function.cc
@@ -302,7 +302,7 @@ bool Table_function_json::init() {
       List_iterator<Json_table_column> li2(m_vt_list);
       // Compare 'first' with all columns prior to it
       while ((col = li2++) && col != first) {
-        if (!strncmp(first->field_name, col->field_name, NAME_CHAR_LEN)) {
+        if (!strncmp(first->field_name, col->field_name, NAME_LEN)) {
           my_error(ER_DUP_FIELDNAME, MYF(0), first->field_name);
           return true;
         }