Re: Thoughts on how to avoid a massive integer update. - Mailing list pgsql-general

From Rob Sargent
Subject Re: Thoughts on how to avoid a massive integer update.
Date
Msg-id 502F77EC-9CEB-4DB6-91D6-3A30F704CF42@gmail.com
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In response to Re: Thoughts on how to avoid a massive integer update.  ("David G. Johnston" <david.g.johnston@gmail.com>)
Responses Re: Thoughts on how to avoid a massive integer update.
List pgsql-general


On May 8, 2020, at 2:57 PM, David G. Johnston <david.g.johnston@gmail.com> wrote:

On Fri, May 8, 2020 at 1:51 PM Rob Sargent <robjsargent@gmail.com> wrote:

On May 8, 2020, at 2:43 PM, David G. Johnston <david.g.johnston@gmail.com> wrote:

On Fri, May 8, 2020 at 1:41 PM Rob Sargent <robjsargent@gmail.com> wrote:
My understanding is the keys in the info_table need to change.  That causes the very expensive update in the update in the data tables. No? 

The keys in the info_table need to change because their contents are no longer legal to be stored (OP has not specified but think using an integer value of someones social security number as a key).  The FK side of the relationship equality has the same illegal data values problem and need to be changed too.

Wow, I couldn’t disagree more ;)

Your agreement or disagreement with the problem statement is immaterial here - the OP has stated what the requirement, for which I have made a simplistic analogy in order to try and get the point across to you.  As the OP has said it is a poor design - and now it is being corrected.  The request is whether there is some way to do so better than the two options the OP already described.

David J.

Sorry, I wasn’t disagreeing with the problem statement. OP did say the “info.id” needed to change from 123 to 456.  With the current foreign key alignment that is very expensive.  I think we’re all in agreement there.  To push “456” back out to the data table I see as perpetuation of the problem.  I didn’t sense that OP felt it necessary to continue in the current mode as a requirement.  If so, my mistake

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