Use of subqueries

    <!-- Query list -->
    <select id="selMap" parameterType="java.util.HashMap" resultType="java.util.HashMap">
        SELECT
            a.id,
            a.building_name,
            a.number_floor,
            DATE_FORMAT( a.create_time, "%Y-%m-%d " ) AS create_time,
        ( SELECT count( 1 ) FROM yz_install_mountingpoint WHERE name_id = a.id ) AS 'cOunt',
        ( SELECT count( 1 ) FROM yz_install_placefloor WHERE building_name = a.id ) AS 'cOuntfloor',
            address,
            dept_name
        FROM
            yz_install_placemanage a,
            sys_dept d
        WHERE
        d.dept_id = a.dept_id
            <include refid="selwhere"/>
            LIMIT #{StarRow},#{PageSize}
    </select>