<insert id="addUserData" parameterType="java.util.List">

    INSERT INTO T_P_USER_DATA (USER_ID, DEPART_ID)

    <foreach collection="list" item="item" index="index" separator=" UNION ALL ">

    SELECT #{item.userId}, #{item.departId} FROM DUAL

    </foreach>

</insert> 

<insert id="addUserData" parameterType="java.util.List">

    INSERT INTO T_P_USER_DATA (USER_ID, DEPART_ID)

    VALUES <foreach collection="list" item="item" index="index"

    separator=",">

    ( #{item.userId}, #{item.departId})

    </foreach>

</insert>