Re: In-place upgrade: catalog side

Greg Smith <gsmith(at)gregsmith(dot)com> writes:

>> I'm sorry, I think I misunderstood the original idea, what you're talking
>> about makes a lot more sense now. You want to save the space of the dead
>> column by replacing it with NULL, not remove it from the table definition.
>
> Not so much to save the space, it's more about breaking its need for the soon
> to be removed pg_attribute that used to lead to the dropped column. If you
> think it's possible to slip that change into the page conversion task, that's
> probably the ideal way to deal with this.

Removing the dropped column attribute is what I think we cannot do. If you
crashed while during that it would leave you with half the table with the
columns in the old attribute position and half the columns in the new
attribute position. There would be no way to tell which was which.

--
Gregory Stark
EnterpriseDB http://www.enterprisedb.com
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