docs: refine taosbenchmark json drop

docs/en/14-reference/05-taosbenchmark.md

@@ -231,7 +231,7 @@ The parameters related to database creation are configured in `dbinfo` in the js
 
 - **name**: specify the name of the database.
 
-- **drop**: indicate whether to delete the database before inserting. The default is true.
+- **drop**: indicate whether to delete the database before inserting. The value can be 'yes' or 'no'. No means do not drop. The default is to drop.
 
 #### Stream processing related configuration parameters
 

docs/zh/14-reference/05-taosbenchmark.md

@@ -231,7 +231,7 @@ taosBenchmark -A INT,DOUBLE,NCHAR,BINARY\(16\)
 
 - **name** : 数据库名。
 
-- **drop** : 插入前是否删除数据库，默认为 true。
+- **drop** : 插入前是否删除数据库，可选项为 "yes" 或者 "no", 为 "no" 时不创建。默认删除。
 
 #### 流式计算相关配置参数