Re: Re: ALTER TABLE ADD CONSTRAINT

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От Jeff Daugherty
Тема Re: Re: ALTER TABLE ADD CONSTRAINT
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Msg-id 3AFC3D88.9050007@greatbridge.com
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Ответ на ALTER TABLE ADD CONSTRAINT  ("Ian Harding" <ianh@co.pierce.wa.us>)
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>> Also, I see that alter table add constraint does not work for defaults.
>>
>> Is this something that is going to be added?
>
> That I do hope will be added since the only way to replicate the
> functionality is to drop, readd and repopulate a table.
>
> Greg

I am not sure specifically what you are looking for but you can add a
default value to a column in an ALTER TABLE statement:

ALTER TABLE two ALTER COLUMN col_b SET DEFAULT 1;

Beyond that you can use another ALTER statement to add a Foreign Key
constraint to the column:

ALTER TABLE two ADD CONSTRAINT two_fk foreign key(col_b) REFERENCES
tbl_one(col_a) match full;

The biggest thing that I have noticed is many things require you to use
separate ALTER statements in order for them to work.

I hope this helps.

jeff


Jeff Daugherty
Database Systems Engineer
Great Bridge, LLC


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