Re: Avoid index rebuilds for no-rewrite ALTER TABLE ALTER TYPE

On mån, 2011-07-18 at 11:05 -0400, Robert Haas wrote:
> On Thu, Jul 7, 2011 at 3:25 PM, Robert Haas <robertmhaas@gmail.com> wrote:
> > On Thu, Jul 7, 2011 at 3:21 PM, Noah Misch <noah@2ndquadrant.com> wrote:
> >> On Thu, Jul 07, 2011 at 03:06:46PM -0400, Robert Haas wrote:
> >>> On Thu, Jul 7, 2011 at 2:55 PM, Noah Misch <noah@2ndquadrant.com> wrote:
> >>> > CheckIndexCompatible() calls ComputeIndexAttrs() to resolve the new operator
> >>> > classes, collations and exclusion operators for each index column.  It then
> >>> > checks those against the existing values for the same.  I figured that was
> >>> > obvious enough, but do you want a new version noting that?
> >>>
> >>> I guess one question I had was... are we depending on the fact that
> >>> ComputeIndexAttrs() performs a bunch of internal sanity checks?  Or
> >>> are we just expecting those to always pass, and we're going to examine
> >>> the outputs after the fact?
> >>
> >> Those checks can fail; consider an explicit operator class or collation that
> >> does not support the destination type.  At that stage, we neither rely on those
> >> checks nor mind if they do fire.  If we somehow miss the problem at that stage,
> >> DefineIndex() will detect it later.  Likewise, if we hit an error in
> >> CheckIndexCompatible(), we would also hit it later in DefineIndex().
> >
> > OK.
> 
> Committed with minor comment and documentation changes.

Please review and fix this compiler warning:

indexcmds.c: In function ‘CheckIndexCompatible’:
indexcmds.c:126:15: warning: variable ‘amoptions’ set but not used [-Wunused-but-set-variable]