of an index can now be a computed expression instead of a simple variable.
Restrictions on expressions are the same as for predicates (only immutable
functions, no sub-selects). This fixes problems recently introduced with
inlining SQL functions, because the inlining transformation is applied to
both expression trees so the planner can still match them up. Along the
way, improve efficiency of handling index predicates (both predicates and
index expressions are now cached by the relcache) and fix 7.3 oversight
that didn't record dependencies of predicate expressions.
review/feedback if anyone is interested and can spend the time. But I'd
also love to get this committed and address changes as incremental
patches ;-), so if there are no objections, please apply.
Below I'll give a synopsis of the changes. More detailed descriptions
are now in a new doc directory under contrib/dblink. There is also a new
dblink.test.sql file which will give a pretty good overview of the
functions and their use.
Joe Conway
array header, and to compute sizing and alignment of array elements
the same way normal tuple access operations do --- viz, using the
tupmacs.h macros att_addlength and att_align. This makes the world
safe for arrays of cstrings or intervals, and should make it much
easier to write array-type-polymorphic functions; as examples see
the cleanups of array_out and contrib/array_iterator. By Joe Conway
and Tom Lane.
code review by Tom Lane. Remaining issues: functions that take or
return tuple types are likely to break if one drops (or adds!)
a column in the table defining the type. Need to think about what
to do here.
Along the way: some code review for recent COPY changes; mark system
columns attnotnull = true where appropriate, per discussion a month ago.
yesterday's proposal to pghackers. Also remove unnecessary parameters
to heap_beginscan, heap_rescan. I modified pg_proc.h to reflect the
new numbers of parameters for the AM interface routines, but did not
force an initdb because nothing actually looks at those fields.
objections.
Major changes:
- removed cursor wrap around input sql to allow for remote
execution of INSERT/UPDATE/DELETE
- dblink now returns a resource id instead of a real pointer
- added several utility functions
I'm still hoping to add explicit cursor open/fetch/close support before
7.3 is released, but I need a bit more time on that.
On a somewhat unrelated topic, I never got any feedback on the
unknownin/out patch and the mb_substring patch. Is there anything else I
need to do to get those applied?
Joe Conway
Tom Lane