('SELECT expression') inline, like macros, during the constant-folding
phase of planning. The actual expansion is not difficult, but checking
that we're not changing the semantics of the call turns out to be more
subtle than one might think; in particular must pay attention to
permissions issues, strictness, and volatility.
well as function calls. This is needed for cases where the planner has
constant-folded or inlined the original function call. Possibly we should
back-patch this change into 7.3 branch as well.
and eliminate its manual pfree() calls. This solves the encoding-conversion
bug recently reported, and should be faster and more robust than the
original coding anyway. For example, we are no longer at risk if
datatype output routines leak memory or choose to return a constant string.
logic, dissuade planner from thinking that 'x IS DISTINCT FROM 42' may
be optimized into 'x = 42' (!!), cause dependency on = operator to be
recorded correctly, minor other improvements.
instead of only one. This should speed up planning (only one hash path
to consider for a given pair of relations) as well as allow more effective
hashing, when there are multiple hashable joinclauses.
operations: make sure we use operators that are compatible, as determined
by a mergejoin link in pg_operator. Also, add code to planner to ensure
we don't try to use hashed grouping when the grouping operators aren't
marked hashable.
sublink results and COPY's domain constraint checking. A Const that
isn't really constant is just a Bad Idea(tm). Remove hacks in
parse_coerce and other places that were needed because of the former
klugery.
just done for copyfuncs/equalfuncs. Read functions in particular get
a lot shorter than before, and it's much easier to compare an out function
with the corresponding read function to make sure they agree.
initdb forced due to small changes in nodestring format (regularizing
a few cases that were formerly idiosyncratic).
reliance on macros, in hopes of eliminating silly typos (like copying
to the wrong field) and just generally making it easier to see the forest
instead of the trees. As an example, here is the new code for A_Indices:
static A_Indices *
_copyAIndices(A_Indices *from)
{
A_Indices *newnode = makeNode(A_Indices);
COPY_NODE_FIELD(lidx);
COPY_NODE_FIELD(uidx);
return newnode;
}
static bool
_equalAIndices(A_Indices *a, A_Indices *b)
{
COMPARE_NODE_FIELD(lidx);
COMPARE_NODE_FIELD(uidx);
return true;
}
I plan to redo outfuncs/readfuncs in a similar style, but am committing
what I've got.
raises pgdb.DatabaseError when any of the fetch*
methods was invoked but previous call to execute* did
not produce any result set or no call was issued yet.
Also, raises pgdb.NotSupportedError when .nextset() is
invoked, instead of NameError.
This behaviour complies with DB-API 2.0.
Thanks for your work!
Timur Irmatov.
used for the primary key lookup. This will prevent a database lookup
for each connection object that gets created. This could be a significant
optimization on a busy system.
Similarly, the get_attnames method allows for the attributes dictionary
to be installed directly.
debug output is managed. The user can continue to use the current method
of passing a formatting string to have a replacement done and output will
be sent to the standard output exactly as it did before. In addition they
can set it to a file object, sys.stderr for example, and the query string
will be printed to it. Thay can also set it to a method (function) and the
query string will be passed to that method giving them the maximum flexibility
to do whatever they want with the query string.
I will be working with the PyGreSQL documentation shortly and at that time
will properly document this feature.
joinclauses is determined accurately for each join. Formerly, the code only
considered joinclauses that used all of the rels from the outer side of the
join; thus for example
FROM (a CROSS JOIN b) JOIN c ON (c.f1 = a.x AND c.f2 = b.y)
could not exploit a two-column index on c(f1,f2), since neither of the
qual clauses would be in the joininfo list it looked in. The new code does
this correctly, and also is able to eliminate redundant clauses, thus fixing
the problem noted 24-Oct-02 by Hans-Jürgen Schönig.
-hackers a couple days ago.
Notes/caveats:
- added regression tests for the new functionality, all
regression tests pass on my machine
- added pg_dump support
- updated PL/PgSQL to support per-statement triggers; didn't
look at the other procedural languages.
- there's (even) more code duplication in trigger.c than there
was previously. Any suggestions on how to refactor the
ExecXXXTriggers() functions to reuse more code would be
welcome -- I took a brief look at it, but couldn't see an
easy way to do it (there are several subtly-different
versions of the code in question)
- updated the documentation. I also took the liberty of
removing a big chunk of duplicated syntax documentation in
the Programmer's Guide on triggers, and moving that
information to the CREATE TRIGGER reference page.
- I also included some spelling fixes and similar small
cleanups I noticed while making the changes. If you'd like
me to split those into a separate patch, let me know.
Neil Conway
