Thread: schema-qualified SET CONSTRAINTS

schema-qualified SET CONSTRAINTS

From
Kris Jurka
Date:
The attached patch allows SET CONSTRAINTS to take a schema qualified
constraint name (myschema.t1_fk_t2) and when given a bare constraint name
it uses the search_path to determine the matching constraint instead of
the previous behavior of disabling all identically named constraints.

Kris Jurka

Attachment

Re: schema-qualified SET CONSTRAINTS

From
Tom Lane
Date:
Kris Jurka <books@ejurka.com> writes:
> The attached patch allows SET CONSTRAINTS to take a schema qualified
> constraint name (myschema.t1_fk_t2) and when given a bare constraint name
> it uses the search_path to determine the matching constraint instead of
> the previous behavior of disabling all identically named constraints.

This patch seems egregiously non backwards compatible :-(.  A behavior
that would be backwards compatible is to retain the previous behavior
given an un-qualified name, while if given a schema-qualified name,
modify all matching constraints within that schema.  That doesn't seem
very self-consistent though.  A compromise that might succeed in making
*everybody* unhappy would be for the unqualified-name case to only
affect constraints that are visible in the current search path (but
affect all of them, not only one as in this patch).

Given the fundamental point that we don't insist on uniqueness of
constraint names within schemas, I'm not sure that the spec gives us
any useful guidance on what SET CONSTRAINTS should affect.

Anyway, I'm not sure what to do, but I am sure it requires some
discussion not just a patch.

            regards, tom lane

Re: schema-qualified SET CONSTRAINTS

From
Bruce Momjian
Date:
Based on discussion, it seems the idea of using search path seems
accepted.

Your patch has been added to the PostgreSQL unapplied patches list at:

    http://momjian.postgresql.org/cgi-bin/pgpatches

It will be applied as soon as one of the PostgreSQL committers reviews
and approves it.

---------------------------------------------------------------------------


Kris Jurka wrote:
>
> The attached patch allows SET CONSTRAINTS to take a schema qualified
> constraint name (myschema.t1_fk_t2) and when given a bare constraint name
> it uses the search_path to determine the matching constraint instead of
> the previous behavior of disabling all identically named constraints.
>
> Kris Jurka

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--
  Bruce Momjian   http://candle.pha.pa.us
  EnterpriseDB    http://www.enterprisedb.com

  + If your life is a hard drive, Christ can be your backup. +

Re: schema-qualified SET CONSTRAINTS

From
Bruce Momjian
Date:
Patch applied.  Thanks.  I also updated our SGML documentation:

    The current schema search path is used to find the first matching name
    if no schema name is specified.

---------------------------------------------------------------------------


Kris Jurka wrote:
>
> The attached patch allows SET CONSTRAINTS to take a schema qualified
> constraint name (myschema.t1_fk_t2) and when given a bare constraint name
> it uses the search_path to determine the matching constraint instead of
> the previous behavior of disabling all identically named constraints.
>
> Kris Jurka

Content-Description:

[ Attachment, skipping... ]

--
  Bruce Momjian   http://candle.pha.pa.us
  EnterpriseDB    http://www.enterprisedb.com

  + If your life is a hard drive, Christ can be your backup. +