Message-ID: <3AD738DB.B90D7866@middle.net>
Date: Fri, 13 Apr 2001 11:35:23 -0600
From: Mark Butler <butlerm@middle.net>
MIME-Version: 1.0
To: Tom Lane <tgl@sss.pgh.pa.us>
CC: pgsql-docs@postgresql.org
Subject: Re: Function Inheritance?
References: <3AD28152.5B88F069@middle.net> <4678.987180995@sss.pgh.pa.us>
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[Re: Tom Lane's explanation of function inheritance]

That is a really nice capability.  However, the statement is somewhat
confusing because this is a matter of parameter type promotion rather than
member/method function inheritance, which is what I thought was being referred
to.

I suggest something like the following:

"In Postgres, each created table automatically defines a new row object type
in an inheritance hierarchy.  Postgres automatically allows a descendant table
row object to be used anywhere a parent table row object is called for.  This
means that functions declared to accept row objects from a parent table
automatically accept row objects from all of its descendant tables as well."

Is that an improvement?  I believe the SQL3 people were wrestling with similar
nomenclature issues once upon a time...

 - Mark Butler