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

Hi Aaron,

I'm using PHP5 as the programming language.

On Thursday 02 November 2006 16:58, Aaron Bono wrote:
> On 11/2/06, Peter Hanson <lists@pkhanson.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.