MyBatis SQL分页处理及查询总数据量

查询数据总数：
<select id="selectCount" resultType="java.lang.Integer">
    <!-- WARNING - @mbggenerated This element is automatically generated by MyBatis Generator, do not modify. --> select count(id) from tb_user <where >
      <if test="username != null" > and username like '%${username,jdbcType=VARCHAR}%'
      </if>
      <if test="start_time != null" > and addtime &gt;= #{start_time,jdbcType=TIMESTAMP} </if>
      <if test="end_time != null" > and addtime &lt;= #{end_time,jdbcType=TIMESTAMP} </if>
    </where>
  </select>

分页查询：
  <select id="getUserForPage" resultMap="BaseResultMap"  >
    <!-- WARNING - @mbggenerated This element is automatically generated by MyBatis Generator, do not modify. --> select <include refid="Base_Column_List" /> from tb_user <where >
      <if test="username != null" > and username like '%${username,jdbcType=VARCHAR}%'
      </if>
      <if test="start_time != null" > and addtime &gt;= #{start_time,jdbcType=TIMESTAMP} </if>
      <if test="end_time != null" > and addtime &lt;= #{end_time,jdbcType=TIMESTAMP} </if>
    </where> limit #{index},#{num} </select>