function as a special case.
This version still has the suspicious behavior of returning null for an
empty array (rather than zero), but this may need a wholesale revision of
empty array behavior, currently under discussion.
Jim Nasby, Robert Haas, Peter Eisentraut
and views (but not system catalogs, nor sequences or toast tables). Get rid
of the hardwired convention that a type's array type is named exactly "_type",
instead using a new column pg_type.typarray to provide the linkage. (It still
will be named "_type", though, except in odd corner cases such as
maximum-length type names.)
Along the way, make tracking of owner and schema dependencies for types more
uniform: a type directly created by the user has these dependencies, while a
table rowtype or auto-generated array type does not have them, but depends on
its parent object instead.
David Fetter, Andrew Dunstan, Tom Lane
Standard English uses "may", "can", and "might" in different ways:
may - permission, "You may borrow my rake."
can - ability, "I can lift that log."
might - possibility, "It might rain today."
Unfortunately, in conversational English, their use is often mixed, as
in, "You may use this variable to do X", when in fact, "can" is a better
choice. Similarly, "It may crash" is better stated, "It might crash".
Also update two error messages mentioned in the documenation to match.
more, and standard_conforming_strings less, because in the future non-E
strings will not treat backslashes specially.
Also use E'' strings where backslashes are used in examples. (The
existing examples would have drawn warnings.)
Backpatch to 8.2.X.
present; intervening positions are filled with nulls. This behavior
is required by SQL99 but was not implementable before 8.2 due to lack
of support for nulls in arrays. I have only made it work for the
one-dimensional case, which is all that SQL99 requires. It seems quite
complex to get it right in higher dimensions, and since we never allowed
extension at all in higher dimensions, I think that must count as a
future feature addition not a bug fix.
compatibility for release 7.2 and earlier. I have not altered any
mentions of release 7.3 or later. The release notes were not modified,
so the changes are still documented, just not in the main docs.
the array (for array_push) or higher-dimensional array (for array_cat)
rather than decrementing it as before. This avoids generating lower
bounds other than one for any array operation within the SQL spec. Per
recent discussion.
Interestingly, this seems to have been the original behavior, because
while updating the docs I noticed that a large fraction of relevant
examples were *wrong* for the old behavior and are now right. Is it
worth correcting this in the back-branch docs?
functionality, but I still need to make another pass looking at places
that incidentally use arrays (such as ACL manipulation) to make sure they
are null-safe. Contrib needs work too.
I have not changed the behaviors that are still under discussion about
array comparison and what to do with lower bounds.
necessary, and be careful to refer to the right version where it is
useful to do so. This partially reverts an ill-considered search and
replace from a few months ago.
was previously allowed in odd places with odd results now causes an ERROR.
Also changed behavior with respect to whitespace -- trailing whitespace is
now ignored as well as leading whitespace (which has always been ignored).
Documentation updated to reflect change in whitespace handling. Also some
refactoring to what I believe is a more sensible order of several paragraphs.
subarrays of a given dimension have the same number of elements/subarrays.
Also repair a longstanding undocumented (as far as I can see) ability to
explicitly set array bounds in the array literal syntax. It now can
deal properly with negative array indicies. Modify array_out so that
arrays with non-standard lower bounds (i.e. not 1) are output with
the expicit dimension syntax. This fixes a longstanding issue whereby
arrays with non-default lower bounds had them changed to default
after a dump/reload cycle.
Modify regression tests and docs to suit, and add some minimal
documentation regarding the explicit dimension syntax.
comparison functions), replacing the highly bogus bitwise array_eq. Create
a btree index opclass for ANYARRAY --- it is now possible to create indexes
on array columns.
Arrange to cache the results of catalog lookups across multiple array
operations, instead of repeating the lookups on every call.
Add string_to_array and array_to_string functions.
Remove singleton_array, array_accum, array_assign, and array_subscript
functions, since these were for proof-of-concept and not intended to become
supported functions.
Minor adjustments to behavior in some corner cases with empty or
zero-dimensional arrays.
Joe Conway (with some editorializing by Tom Lane).
Still needs to be filled with more information, but it gives us a
framework to have a User's Guide with complete coverage of the basic
SQL operations. Move arrays into data type chapter, inheritance into
DDL chapter (for now).
Make <comment>s show up in the output while the version number ends in
"devel".
Allow cross-book references with entities &cite-user; etc.
