Re: Safe operations?

On Mon, 13 Aug 2018 at 11:24, Adrian Klaver <adrian(dot)klaver(at)aklaver(dot)com>
wrote:

> On 08/12/2018 05:41 PM, Samuel Williams wrote:
> > I wish the documentation would include performance details, i.e. this
> > operation is O(N) or O(1) relative to the number of rows.
> >
> > I found renaming a table was okay.
> >
> > How about renaming a column? Is it O(1) or proportional to the amount of
> > data?
> >
> > Is there any documentation about this?
>
> https://www.postgresql.org/docs/10/static/sql-altertable.html
>
> "RENAME
>
> The RENAME forms change the name of a table (or an index, sequence,
> view, materialized view, or foreign table), the name of an individual
> column in a table, or the name of a constraint of the table. There is no
> effect on the stored data.
> "
>
> Just wondering - what about the case when the column being renamed is also
> referenced in an index or check constraint? (I would guess you cannot
> rename a column used in a check constraint without first removing it, but
> for an index, would this result in the index being rebuilt (or do you have
> to take care of that manually or are such references abstracted such that
> the column name "text" is irrelevant tot he actual structure of the
> index?).

>
>
> --
> Adrian Klaver
> adrian(dot)klaver(at)aklaver(dot)com
>
>

--
regards,

Tim

--
Tim Cross