Mybatis动态sql条件查询、判断空值和空字符串

@Select("<script>" +
            "SELECT * FROM table_name WHERE 1=1" +
            "<if test='templateCode!=null'>" +
            "and template_code = #{templateCode}" +
            "</if>" +
            "<if test='templateCode==null'>" +
            "and (template_code  IS NULL or template_code='')" +
            "</script>")

templateCode:参数信息
table_name:表名
template_code:数据库列名

以上脚本的功能

当传入templateCode为空时
   则运行sql
select * from table_name 
   where 1=1 
     and (template_code  IS NULL or template_code='');

当传入的templateCode不为空时
    则运行sql
select * from table_name 
    where 1=1 
	  and template_code = #{templateCode};