mybatis在项目中需要注意的事项

1、当传入多个参数时，需要设置各个参数的别名；当传入一个对象，若其参数参与条件判断，需要先判断对象是否为空；若属性为基本数据类型，参与判断，不能对它进行不等于NULL判断，需要转换为包装类。一般创建类时，将属性的类型设置为包装类。

public List<VehicleModel> queryModel(
        @Param("im") VehicleModel model, @Param("startRow") int startRow,
        @Param("endRow") int endRow,@Param("startDate") String startDate,
        @Param("endDate") String endDate,@Param("startPrice") Long startPrice,
        @Param("endPrice") Long endPrice);

<select id="queryModel" resultType="com.lpck.vehicle.pojo.VehicleModel">
        select aaa.*,s.MIN_NAME FROM  (select aa.* from (SELECT rownum rn,a.* from A_MODEL a WHERE 1=1
        <if test="im != null">
            <if test="im.modelCountry != null and im.modelCountry != ''">
                and MODEL_COUNTRY = #{im.modelCountry}
            </if>
            <if test="im.modelStandardName != null and im.modelStandardName != ''">
                and MODEL_STANDARD_NAME LIKE '%${im.modelStandardName}%'
            </if>
            <if test="im.modelFactory != null and im.modelFactory != ''">
                and MODEL_FACTORY LIKE '%${im.modelFactory}%'
            </if>
            <if test="im.modelIsLoss != null">
                and MODEL_IS_LOSS = #{im.modelIsLoss}
            </if>
            <if test="im.modelBrand != null and im.modelBrand != ''">
                and MODEL_BRAND LIKE '%${im.modelBrand}%'
            </if>
            <if test="im.modelCateName != null and im.modelCateName != ''">
                and MODEL_CATE_NAME LIKE '%${im.modelCateName}%'
            </if>
            <if test="im.modelSubClass != null and im.modelSubClass != '' ">
                and MODEL_SUB_CLASS = #{im.modelSubClass}
            </if>
        </if>
        <if test="startDate != null and startDate != ''">
            and MODEL_YEAR >= #{startDate}
        </if>
        <if test="endDate != null and endDate!= ''">
            and MODEL_YEAR &lt;= #{endDate}
        </if>
        <if test="startPrice != null">
            and MODEL_PRICE >= #{startPrice}
        </if>
        <if test="endPrice != null">
            and MODEL_PRICE  &lt;= #{endPrice}
        </if>
        and rownum &lt;= #{endRow})aa
        WHERE aa.rn > #{startRow})aaa
        LEFT JOIN S_DICT_MIN s on aaa.MODEL_SUB_CLASS = s.MIN_VALUE
    </select>