mybatis, mapper.xml file book foreach use

The foreach loop (oracle database) is used when using mybatis to customize SQL in my recent work, but the following writing is not easy to use:

<insert id="insertBatch" parameterType="java.util.List">
        insert INTO
        user_tb
        (user_id,
        user_name,
        user_age)
        <foreach collection="list" item="item" separator="union all">
            select
            #{item.userId},
            #{item.userName},
            #{item.userAge}
            FROM dual
        </foreach>
    </insert>

A colleague reminded me to write:

<insert id="insertBatch" parameterType="java.util.List" useGeneratedKeys="false">
        insert INTO
        user_tb
        (user_id,
        user_name,
        user_age)
        <foreach collection="list" item="item" separator="union all">
            select
            #{item.userId},
            #{item.userName},
            #{item.userAge}
            FROM dual
        </foreach>
    </insert>

The use of self-incrementing primary keys in oracle database requires the use of sequences or other methods, and does not support automatic generation.