Re: Converting char to varchar automatically - Mailing list pgsql-general

From Sergey Konoplev
Subject Re: Converting char to varchar automatically
Date
Msg-id CAL_0b1vPsD1EpvkqO3M0LF2raRFj8hes=70F2w20=RxbpH1aNQ@mail.gmail.com
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In response to Re: Converting char to varchar automatically  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Converting char to varchar automatically  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
BTW, where can I find a list of type1->type2 pairs that doesn't
require full table lock for conversion?

ps. Sorry for top posting.

On Mon, Oct 6, 2014 at 4:20 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Melvin Davidson <melvin6925@gmail.com> writes:
>> Also, don't forget to test for relkind = 'r'. My bad from before.
>
> In principle you need to ignore attisdropped columns as well.
>
> Thinking about Jim's point about speed: it'd be wise to collapse any
> updates for multiple columns in the same table into one ALTER command,
> so that you only rewrite the table once, not once per column.
>
>                         regards, tom lane
>
>
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--
Kind regards,
Sergey Konoplev
PostgreSQL Consultant and DBA

http://www.linkedin.com/in/grayhemp
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