sql - What GUID can I use as a placeholder -

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i have database table has non null column of type uniqueidentifier. put in place use in near future. now, need use placeholder. can use:

00000000-0000-0000-0000-000000000000

for rows until real guid used when new rows inserted in future? sql server enforce uniqueness on column?

sql server enforce uniqueness, if , if you put unique constraint or unique index on field. otherwise, sql server enforce value must not null.


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