RE: I'd like to discuss scaleout at PGCon

From: Michael Paquier [mailto:michael@paquier.xyz]
> > On Wed, Jun 6, 2018 at 8:16 PM, MauMau  wrote:
> >> Looking at the XL source code, the following sequence of functions
> >> are called when the coordinator handles the Row Description message
> >> ('T') from the data node.  I guess the parsing is necessary to
> >> process type names combined with type modifiers, e.g. "char(100)".
> >>
> >>     create_tuple_desc
> >>     parseTypeString
> >>     typeStringToTypeName
> >>     raw_parser
> >
> > Hmm, strange. I had not seen that in Postgres-XC.
> 
> Where is that located in the XC code?  If you point out to the location
> it may revive some past memories from either Ashutosh or me.

The XL-specific code path is this in src/backend/pgxc/pool/execRemote.c (I don't know this also exists in XC):
handle_response -> HandleRowDescription -> create_tuple_desc

I think the rest exists in PostgreSQL:
parseTypeString -> typeStringToTypeName -> raw_parser

Regards
Takayuki Tsunakawa