mybatis之The expression 'oredCriteria' evaluated to a null value的解决方法

<if test="example!= null">
      <include refid="Example_Where_Clause" />
</if>

原因：执行过程中，显示在使用example的时候，里面的criteria为null；将上面的XML用下面替换

<if test="_parameter != null" >
      <include refid="Update_By_Example_Where_Clause" />
</if>

例子：

<select id="selectByExampleLimit" resultMap="BaseResultMap">
        select
        <if test="distinct">
            distinct
        </if>
        <include refid="Base_Column_List" />
        from Test
        <if test="_parameter != null" >
            <include refid="Update_By_Example_Where_Clause" />
        </if>
        <if test="orderByClause != null">
            order by ${orderByClause}
        </if>
</select>

文章来自：http://www.cnblogs.com/spacewalk/p/3975415.html