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【DM版本】:
【操作系统】：
【CPU】:
【问题描述】*：
SELECT
a.sort AS “sort”,
c.id AS “id”,
c. NAME AS “name”,
c.mailaddr AS “email”,
“3” AS “accountType”,
c.full_name AS “fullName”
FROM WEBADMIN.address_book_dynamic_group_user a
inner JOIN WEBADMIN.sys_maillist c ON c.id = a.user_id

其中想给一个不存在的字段赋值常量怎么写