Re: Updated interval patches (SQL std output, ISO8601 intervals, and interval rounding)

Ron Mayer wrote:
> Tom Lane wrote:
>> In fact, given that we are now
>> somewhat SQL-compliant on interval input, a GUC that selected
>> PG traditional, SQL-standard, or ISO 8601 interval output format seems
>> like it could be a good idea.

Attached are updated versions of the Interval patches (SQL-standard interval
output, ISO8601 intervals, and interval rounding) I posted earlier upthread.
I mostly brought it up-to-date with HEAD, cleaned up comments and regression
tests, and fixed a couple bugs. [Sorry if people get this twice. I tried
attaching all 4 patches earlier today, but didn't notice it on the
list perhaps because of the combined size.]

# Patch 1: "stdintervaloutput.patch"
SQL Standard Interval Literal Output

Description: This patch adds an IntervalStyle GUC to control
the style of intervals. Previously the interval style was a
side-effect of the DateStyle GUC. IntervalStyle can be set to
"sql_standard" to output SQL Standard Interval Literals.

Reason for the patch: Now that we support SQL-standard interval
inputs, it's nice to be able to output intervals in that style as well.

During the commit-fest I'll post versions of these that are regularly
synced with CVS HEAD here: http://0ape.com/postgres_interval_patches/