Request a Demo
Home   >   mailing lists

Re: in the different schema ，the sequence name is same， and a table's column definition use this sequence,so，how can I identify sequence's schema name by system view/table: - Mailing list pgsql-docs

From David G. Johnston
Subject Re: in the different schema ，the sequence name is same， and a table's column definition use this sequence,so，how can I identify sequence's schema name by system view/table:
Date
Msg-id CAKFQuwbTyugCotCc5dE-5Njy3MG3ZVgDd2c_J9=fU541dnaOWA@mail.gmail.com
Whole thread Raw
In response to Re: in the different schema ，the sequence name is same， and a table's column definition use this sequence,so，how can I identify sequence's schema name by system view/table:  ("David G. Johnston" <david.g.johnston@gmail.com>)
List pgsql-docs
Tree view
On Wednesday, October 1, 2025, David G. Johnston <david.g.johnston@gmail.com> wrote:
On Wednesday, October 1, 2025, yanliang lei <msdnchina@163.com> wrote:
dbversion180=# create table schema_1.test_tab_100(c1 int default nextval('seq_xx_yy'));

Since you didn’t schema qualify the sequence name every single time a default value is created the sequence will be looked up anew.  The stored expression is not associated with any specific object.

This is also why there is a separate step to mark a sequence as being owned by a table.  That establishes a dependency that this textual form is unable to do.

 
 Ignore that…we do stored the parsed representation which nominally has the schema recorded, it’s just that the text serialization it too “helpful” by inspecting the search_path and only produces the schema prefix if it would be necessary to resolve the reference.

David J.

pgsql-docs by date:

Previous
From: "David G. Johnston"
Date:
Subject: Re: in the different schema ，the sequence name is same， and a table's column definition use this sequence,so，how can I identify sequence's schema name by system view/table: