My team meet a performance issue of mybatis 3.5.3, execute a simple select from mysql which takes about 15 seconds. The result of this query is a List<Map>, and the count of the list is 150. The mapper is as follow:
<select id = 'selectMapList' reusltMap='mainMap'>
select #90 properties# from table where #condition#
</select>
<resultMap id = 'mainMap' type='java.util.Map'>
#90 <result> label #
</resultMap>
But when I update the version to 3.5.4, it works fine. I have traced the source code and found DefaultResultSetHandler#handleRowValuesForSimpleResultMap method cost too much time, but I can't found the root cause of this scenario. Could somebody help me about this? thx.