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:
>
> 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.

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