Re: Determining correct table order for insert or drop statements to satisfy foreign keys

On 11/2/06, Peter Hanson <lists(at)pkhanson(dot)com> wrote:
>
> Hi Aaron,
>
> I'm using PHP5 as the programming language.

Unfortunately it looks like PHP has very limited support for meta data:
http://us2.php.net/manual/en/function.pg-meta-data.php

Check this out:
http://www.postgresql.org/docs/8.0/interactive/functions-info.html
http://archives.postgresql.org/pgsql-admin/2006-08/msg00147.php

See if that points you in the right direction.

On Thursday 02 November 2006 16:58, Aaron Bono wrote:
> > On 11/2/06, Peter Hanson <lists(at)pkhanson(dot)com> wrote:
> > > Hello,
> > >
> > > First, sorry if this has already been covered, though I didn't find
> > > anything
> > > similar in the archives. Also sorry if this is the wrong list for this
> > > type
> > > of question, though it seemed to be the most relevant list for this
> > > question.
> > >
> > > On to the question:
> > >
> > > I'm writing a simple import script that reads in an excel file that a
> > > customer
> > > fills out. Each worksheet represents a different table and the tables'
> > > fields
> > > are columns in each worksheet.
> > >
> > > The tables represented in the file are variable, I have no idea what
> > > table combinations will be in the excel file when it's sent to the
> > > script.
> > >
> > > What I need is a way for the script to determine what order it should
> > > process
> > > the worksheets in the excel file.
> > >
> > > For example, you have this table structure (each table would be a
> > > worksheet):
> > >
> > > PERSON (1) <--> (many) ORDER (1) <--> (many) ORDER_ITEM
> > >
> > > Obviously, the people would have to be inserted first, then the
> orders,
> > > and
> > > finally the items, to keep the foreign keys between the tables happy.
> > >
> > > Is there a mechanism in PostgreSQL that would tell me this order? Or
> is
> > > it
> > > something that would have to be assembled from analyzing the
> > > schema? Anybody
> > > needed to perform an operation like this before? Any help/direction
> would
> > > be
> > > greatly appreciated.
> >
> > What programming language are you using? Many languages provide
> mechanisms
> > to ask the database for metadata about tables including primary keys,
> > indexes, data types and foreign keys. That is one option for you.

--
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Aaron Bono
Aranya Software Technologies, Inc.
http://www.aranya.com
http://codeelixir.com
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