subselects can only appear on the righthand side of a binary operator.
That's still true for quantified predicates like x = ANY (SELECT ...),
but a subselect that delivers a single result can now appear anywhere
in an expression. This is implemented by changing EXPR_SUBLINK sublinks
to represent just the (SELECT ...) expression, without any 'left hand
side' or combining operator --- so they're now more like EXISTS_SUBLINK.
To handle the case of '(x, y, z) = (SELECT ...)', I added a new sublink
type MULTIEXPR_SUBLINK, which acts just like EXPR_SUBLINK used to.
But the grammar will only generate one for a multiple-left-hand-side
row expression.
circumstances:
=> select * from foo\x\t\pset border 0 \p\g\\select * from bar;
Also the release prep update so the sql_help.h is generated before
packaging.
Peter.
nulls with non-nulls using proper three-valued boolean logic. Also clean
up ExecQual to make it clearer that ExecQual *does* follow the SQL spec
for boolean nulls. See '[BUGS] (null) != (null)' thread around 10/26/99
for more detail.
* Add use of 'const' for varibles in source tree
(which is misspelled, btw.)
I went through the front-end libpq code and did so. This affects in
particular the various accessor functions (such as PQdb() and
PQgetvalue()) as well as, by necessity, the internal helpers they use.
I have been really thorough in that regard, perhaps some people will find
it annoying that things like
char * foo = PQgetvalue(res, 0, 0)
will generate a warning. On the other hand it _should_ generate one. This
is no real compatibility break, although a few clients will have to be
fixed to suppress warnings. (Which again would be in the spirit of the
above TODO.)
In addition I replaced some int's by size_t's and removed some warnings
(and generated some new ones -- grmpf!). Also I rewrote PQoidStatus (so it
actually honors the const!) and supplied a new function PQoidValue that
returns a proper Oid type. This is only front-end stuff, none of the
communicaton stuff was touched.
The psql patch also adds some new consts to honor the new libpq situation,
as well as fixes a fatal condition that resulted when using the -V
(--version) option and there is no database listening.
So, to summarize, the psql you should definitely put in (with or without
the libpq). If you think I went too far with the const-mania in libpq, let
me know and I'll make adjustments. If you approve it, I will also update
the docs.
-Peter
--
Peter Eisentraut Sernanders vaeg 10:115
Now indexes of pg_class and pg_type are unique indexes
and guarantee the uniqueness of correponding attributes.
heap_create() was changed to take another boolean parameter
which allows to postpone the creation of disk file.
The name of rd_nonameunlinked was changed to rd_unlinked.
It is used generally(not only for noname relations) now.
Requires initdb.
