diff --git a/sql-statements/sql-statement-create-index.md b/sql-statements/sql-statement-create-index.md
index ec42bcc8b8f9d..57b3465825f37 100644
--- a/sql-statements/sql-statement-create-index.md
+++ b/sql-statements/sql-statement-create-index.md
@@ -142,9 +142,9 @@ Expression indexes have the same syntax and limitations as in MySQL. They are im
 
 Currently, the optimizer can use the indexed expressions when the expressions are only in the `FIELD` clause, `WHERE` clause, and `ORDER BY` clause. The `GROUP BY` clause will be supported in future updates.
 
-## Associated session variables
+## Associated system variables
 
-The global variables associated with the `CREATE INDEX` statement are `tidb_ddl_reorg_worker_cnt`, `tidb_ddl_reorg_batch_size` and `tidb_ddl_reorg_priority`. Refer to [system variables](/system-variables.md#tidb_ddl_reorg_worker_cnt) for details.
+The system variables associated with the `CREATE INDEX` statement are `tidb_ddl_reorg_worker_cnt`, `tidb_ddl_reorg_batch_size`, and `tidb_ddl_reorg_priority`. Refer to [system variables](/system-variables.md#tidb_ddl_reorg_worker_cnt) for details.
 
 ## MySQL compatibility