mybatis 如何通過(guò)resultMap 返回long
<resultMap type='java.lang.Long'> <result column='budget' property='budget' javaType='long'/> </resultMap> mybatis long 類型返回為null報(bào)異常
Mapper method ’com.mpn.dao.TWeatherMapper.avgWeatherTemperature attempted to return null from a method with a primitive return type (long).
<select resultType='java.lang.Long' parameterType='java.lang.String' >SELECT IFNULL(AVG(WeatherTemperature),0) AS OrderAverage FROM t_weather WHERE WeatherDate= #{date,jdbcType=VARCHAR}; </select> <select resultType='java.lang.Long' parameterType='java.lang.String' >SELECT SUM(WeatherTemperature) AS OrderAverage FROM t_weather WHERE WeatherDate= #{date,jdbcType=VARCHAR}; </select> <select resultType='java.lang.Long' parameterType='java.lang.String' >SELECT IFNULL(AVG(WeatherHumidity),0) AS OrderAverage FROM t_weather WHERE WeatherDate= #{date,jdbcType=VARCHAR}; </select>
由于返回為空l(shuí)ong中沒(méi)有此類型所以拋異常,改為
<!-- 根據(jù)日期來(lái)進(jìn)行計(jì)算平局值與 --> <select resultType='java.lang.Long' parameterType='java.lang.String' >SELECT IFNULL(AVG(WeatherTemperature),0) AS OrderAverage FROM t_weather WHERE WeatherDate= #{date,jdbcType=VARCHAR}; </select> <select resultType='java.lang.Long' parameterType='java.lang.String' >SELECT IFNULL(SUM(WeatherTemperature),0) AS OrderAverage FROM t_weather WHERE WeatherDate= #{date,jdbcType=VARCHAR}; </select> <select resultType='java.lang.Long' parameterType='java.lang.String' >SELECT IFNULL(AVG(WeatherHumidity),0) AS OrderAverage FROM t_weather WHERE WeatherDate= #{date,jdbcType=VARCHAR}; </select>
用IFNULL來(lái)進(jìn)行判斷!
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