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From: Matthew Denny <mdenny@CS.Berkeley.EDU>
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Date: Sun, 16 Apr 2000 11:57:38 -0700 (PDT)
To: pgsql-interfaces@postgresql.org, pgsql-novice@postgresql.org
Subject: a couple of newbie question
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I know this question is probably fairly elementary, but I could not
find the answer in the docs or mailing list archives.  How does one handle
NULL values in the embedded SQL interface?  For example, if I have a
statement:

exec sql insert into test_table values(:foo, :x, :y)

and foo represents a CHAR attribute (represented by a string in C) that I
want to set to NULL, how do I go about doing this?  Similarly, how do
I tell that a value put into a variable by a fetch call is NULL or
not?  

On a different note, is there any list of error codes for the actual
postgreSQL errors, or is the only thing a user can get back is the
text message in sqlca.sqlerrm.sqlerrmc (e.g. no associated error #)?

Any help would be greatly appreciated.

thanks,
Matt