<updateid="batchUpdateUserInfoByIdAndUserName">
UPDATE user
SET
age =
<foreachcollection="list"item="item"open="case "close=" end,">
when id=#{item.id}
and username=#{item.username}
then #{item.age}
</foreach>
sex =
<foreachcollection="list"item="item"open="case "close=" end,">
when id=#{item.id}
and username=#{item.username}
then #{item.sex}
</foreach>
where id in
<foreachcollection="list"item="item"index="index"open="("separator=","close=")">
#{item.id}
</foreach>
AND username in
<foreachcollection="list"item="item"index="index"open="("separator=","close=")">
#{item.username}
</foreach></update>