Re: Binary tx format for an array?

[Dave Cramer <pg(at)fastcrypt(dot)com>]

On 23-Jun-06, at 8:56 AM, Dave Cramer wrote:

> On 23-Jun-06, at 8:47 AM, Michael Guyver wrote:
>
> > > > :) good question, I'm sure I'll stare it in the face soon  
> > > enough. At
> > > > the moment I'm labouring under the impression that individual
> > > > parameters can be specified as binary or text.
> > >
> > > Unfortunately this is not possible. :( And one of the reasons that
> > > I've not spent a lot of time on this.
> >
> > Hi Dave,
> >
> > the page Message Formats
> > (http://www.postgresql.org/docs/8.1/static/protocol-message- 
> > formats.html)
> > specifies that the bind message should send the following for each
> > parameter:
> >
> >    Int16 - The number of parameter format codes that follow (denoted
> > C below). This can be zero to indicate that there are no  
> > parameters or
> > that the parameters all use the default format (text); or one, in
> > which case the specified format code is applied to all parameters; or
> > it can equal the actual number of parameters.
> >
> >    Int16[C] - The parameter format codes. Each must presently be zero
> > (text) or one (binary).
> >
> > Does your understanding of the spec mean that the Int16[C] must  
> > either
> > be an array containg all zero's, or all ones? It reads as though  
> > these
> > can be mixed.
>
> Actually, it's the return value that is either/or . It appears that  
> input parameters can be mixed.
Hmmm maybe I should read before sending. It appears that both input,  
and output can be text. The only catch with output is that you have  
to do a describe first to get the types. This may negate any gains on  
small result sets, but certainly for large ones it would help.
> Tom can they be mixed going in ?
>
> I'm very curious to see how much performance gain can be had here.  
> As I said the real gains would be on result sets especially parsing  
> date/time, timestamps.
> >
>
>
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