Re: Retrieving timestamp data - Mailing list pgsql-interfaces

From Michael Fuhr
Subject Re: Retrieving timestamp data
Date
Msg-id 20070304172355.GA38897@winnie.fuhr.org
Whole thread Raw
In response to Retrieving timestamp data  ("::Willi the One::" <sonic_and_tails2000@yahoo.com>)
Responses Re: Retrieving timestamp data  ("::Willi the One::" <sonic_and_tails2000@yahoo.com>)
List pgsql-interfaces
On Sun, Mar 04, 2007 at 07:23:10AM -0800, ::Willi the One:: wrote:
> In the documentation, it says that PQgetvalue()
> returns string values for strings and "the value is in
> the binary representation determined by the data
> type’s typsend and typreceive functions."

You've omitted part of what the documentation says.  The complete
text is:
 For data in text format, the value returned by PQgetvalue is a null-terminated character string representation of the
fieldvalue.  For data in binary format, the value is in the binary representation determined by the data type's typsend
andtypreceive functions.
 

> The problem is, where's the typsend and typrecieve located?

In the backend.  You can find out which functions they are by
querying pg_type, and you can learn more about the functions
themselves by querying pg_proc and by examining the source code.
But you should only need to do this if you need query results in
binary format.  Do you?

> For example, if I want to retrieve a timestamp data,
> how would I do it? Will it return as a string when I
> call PQgetvalue()? What about other types such Points
> or inet types?

Unless you request results in binary format all values will be
returned as text strings.  What happened when you tried it?  Are
you requesting results in binary format?

-- 
Michael Fuhr


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