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2016-07-28Improve documentation about CREATE TABLE ... LIKE.Tom Lane
The docs failed to explain that LIKE INCLUDING INDEXES would not preserve the names of indexes and associated constraints. Also, it wasn't mentioned that EXCLUDE constraints would be copied by this option. The latter oversight seems enough of a documentation bug to justify back-patching. In passing, do some minor copy-editing in the same area, and add an entry for LIKE under "Compatibility", since it's not exactly a faithful implementation of the standard's feature. Discussion: <20160728151154.AABE64016B@smtp.hushmail.com>
2015-03-31Remove spurious semicolons.Heikki Linnakangas
Petr Jelinek
2014-11-12Explicitly support the case that a plancache's raw_parse_tree is NULL.Tom Lane
This only happens if a client issues a Parse message with an empty query string, which is a bit odd; but since it is explicitly called out as legal by our FE/BE protocol spec, we'd probably better continue to allow it. Fix by adding tests everywhere that the raw_parse_tree field is passed to functions that don't or shouldn't accept NULL. Also make it clear in the relevant comments that NULL is an expected case. This reverts commits a73c9dbab0165b3395dfe8a44a7dfd16166963c4 and 2e9650cbcff8c8fb0d9ef807c73a44f241822eee, which fixed specific crash symptoms by hacking things at what now seems to be the wrong end, ie the callee functions. Making the callees allow NULL is superficially more robust, but it's not always true that there is a defensible thing for the callee to do in such cases. The caller has more context and is better able to decide what the empty-query case ought to do. Per followup discussion of bug #11335. Back-patch to 9.2. The code before that is sufficiently different that it would require development of a separate patch, which doesn't seem worthwhile for what is believed to be an essentially cosmetic change.
2014-05-28Revert "Fix bogus %name-prefix option syntax in all our Bison files."Tom Lane
This reverts commit ece7aa8b0f57d92577055a88579555df895eb929. It turns out that the %name-prefix syntax without "=" does not work at all in pre-2.4 Bison. We are not prepared to make such a large jump in minimum required Bison version just to suppress a warning message in a version hardly any developers are using yet. When 3.0 gets more popular, we'll figure out a way to deal with this. In the meantime, BISONFLAGS=-Wno-deprecated is recommendable for anyone using 3.0 who doesn't want to see the warning.
2014-05-28Fix bogus %name-prefix option syntax in all our Bison files.Tom Lane
%name-prefix doesn't use an "=" sign according to the Bison docs, but it silently accepted one anyway, until Bison 3.0. This was originally a typo of mine in commit 012abebab1bc72043f3f670bf32e91ae4ee04bd2, and we seem to have slavishly copied the error into all the other grammar files. Per report from Vik Fearing; analysis by Peter Eisentraut. Back-patch to all active branches, since somebody might try to build a back branch with up-to-date tools.
2014-05-06Remove tabs after spaces in C commentsBruce Momjian
This was not changed in HEAD, but will be done later as part of a pgindent run. Future pgindent runs will also do this. Report by Tom Lane Backpatch through all supported branches, but not HEAD
2014-04-03Fix non-equivalence of VARIADIC and non-VARIADIC function call formats.Tom Lane
For variadic functions (other than VARIADIC ANY), the syntaxes foo(x,y,...) and foo(VARIADIC ARRAY[x,y,...]) should be considered equivalent, since the former is converted to the latter at parse time. They have indeed been equivalent, in all releases before 9.3. However, commit 75b39e790 made an ill-considered decision to record which syntax had been used in FuncExpr nodes, and then to make equal() test that in checking node equality --- which caused the syntaxes to not be seen as equivalent by the planner. This is the underlying cause of bug #9817 from Dmitry Ryabov. It might seem that a quick fix would be to make equal() disregard FuncExpr.funcvariadic, but the same commit made that untenable, because the field actually *is* semantically significant for some VARIADIC ANY functions. This patch instead adopts the approach of redefining funcvariadic (and aggvariadic, in HEAD) as meaning that the last argument is a variadic array, whether it got that way by parser intervention or was supplied explicitly by the user. Therefore the value will always be true for non-ANY variadic functions, restoring the principle of equivalence. (However, the planner will continue to consider use of VARIADIC as a meaningful difference for VARIADIC ANY functions, even though some such functions might disregard it.) In HEAD, this change lets us simplify the decompilation logic in ruleutils.c, since the funcvariadic/aggvariadic flag tells directly whether to print VARIADIC. However, in 9.3 we have to continue to cope with existing stored rules/views that might contain the previous definition. Fortunately, this just means no change in ruleutils.c, since its existing behavior effectively ignores funcvariadic for all cases other than VARIADIC ANY functions. In HEAD, bump catversion to reflect the fact that FuncExpr.funcvariadic changed meanings; this is sort of pro forma, since I don't believe any built-in views are affected. Unfortunately, this patch doesn't magically fix everything for affected 9.3 users. After installing 9.3.5, they might need to recreate their rules/views/indexes containing variadic function calls in order to get everything consistent with the new definition. As in the cited bug, the symptom of a problem would be failure to use a nominally matching index that has a variadic function call in its definition. We'll need to mention this in the 9.3.5 release notes.
2014-02-18Remove broken code that tried to handle OVERLAPS with a single argument.Tom Lane
The SQL standard says that OVERLAPS should have a two-element row constructor on each side. The original coding of OVERLAPS support in our grammar attempted to extend that by allowing a single-element row constructor, which it internally duplicated ... or tried to, anyway. But that code has certainly not worked since our List infrastructure was rewritten in 2004, and I'm none too sure it worked before that. As it stands, it ends up building a List that includes itself, leading to assorted undesirable behaviors later in the parser. Even if it worked as intended, it'd be a bit evil because of the possibility of duplicate evaluation of a volatile function that the user had written only once. Given the lack of documentation, test cases, or complaints, let's just get rid of the idea and only support the standard syntax. While we're at it, improve the error cursor positioning for the wrong-number-of-arguments errors, and inline the makeOverlaps() function since it's only called in one place anyway. Per bug #9227 from Joshua Yanovski. Initial patch by Joshua Yanovski, extended a bit by me.
2014-02-17Avoid repeated name lookups during table and index DDL.Robert Haas
If the name lookups come to different conclusions due to concurrent activity, we might perform some parts of the DDL on a different table than other parts. At least in the case of CREATE INDEX, this can be used to cause the permissions checks to be performed against a different table than the index creation, allowing for a privilege escalation attack. This changes the calling convention for DefineIndex, CreateTrigger, transformIndexStmt, transformAlterTableStmt, CheckIndexCompatible (in 9.2 and newer), and AlterTable (in 9.1 and older). In addition, CheckRelationOwnership is removed in 9.2 and newer and the calling convention is changed in older branches. A field has also been added to the Constraint node (FkConstraint in 8.4). Third-party code calling these functions or using the Constraint node will require updating. Report by Andres Freund. Patch by Robert Haas and Andres Freund, reviewed by Tom Lane. Security: CVE-2014-0062
2014-02-13Separate multixact freezing parameters from xid'sAlvaro Herrera
Previously we were piggybacking on transaction ID parameters to freeze multixacts; but since there isn't necessarily any relationship between rates of Xid and multixact consumption, this turns out not to be a good idea. Therefore, we now have multixact-specific freezing parameters: vacuum_multixact_freeze_min_age: when to remove multis as we come across them in vacuum (default to 5 million, i.e. early in comparison to Xid's default of 50 million) vacuum_multixact_freeze_table_age: when to force whole-table scans instead of scanning only the pages marked as not all visible in visibility map (default to 150 million, same as for Xids). Whichever of both which reaches the 150 million mark earlier will cause a whole-table scan. autovacuum_multixact_freeze_max_age: when for cause emergency, uninterruptible whole-table scans (default to 400 million, double as that for Xids). This means there shouldn't be more frequent emergency vacuuming than previously, unless multixacts are being used very rapidly. Backpatch to 9.3 where multixacts were made to persist enough to require freezing. To avoid an ABI break in 9.3, VacuumStmt has a couple of fields in an unnatural place, and StdRdOptions is split in two so that the newly added fields can go at the end. Patch by me, reviewed by Robert Haas, with additional input from Andres Freund and Tom Lane.
2014-02-13Fix length checking for Unicode identifiers containing escapes (U&"...").Tom Lane
We used the length of the input string, not the de-escaped string, as the trigger for NAMEDATALEN truncation. AFAICS this would only result in sometimes printing a phony truncation warning; but it's just luck that there was no worse problem, since we were violating the API spec for truncate_identifier(). Per bug #9204 from Joshua Yanovski. This has been wrong since the Unicode-identifier support was added, so back-patch to all supported branches.
2014-02-03Fix lexing of U& sequences just before EOF.Tom Lane
Commit a5ff502fceadc7c203b0d7a11b45c73f1b421f69 was a brick shy of a load in the backend lexer too, not just psql. Per further testing of bug #9068. In passing, improve related comments.
2014-01-21Allow type_func_name_keywords in even more placesStephen Frost
A while back, 2c92edad48796119c83d7dbe6c33425d1924626d allowed type_func_name_keywords to be used in more places, including role identifiers. Unfortunately, that commit missed out on cases where name_list was used for lists-of-roles, eg: for DROP ROLE. This resulted in the unfortunate situation that you could CREATE a role with a type_func_name_keywords-allowed identifier, but not DROP it (directly- ALTER could be used to rename it to something which could be DROP'd). This extends allowing type_func_name_keywords to places where role lists can be used. Back-patch to 9.0, as 2c92edad48796119c83d7dbe6c33425d1924626d was.
2014-01-21Tweak parse location assignment for CURRENT_DATE and related constructs.Tom Lane
All these constructs generate parse trees consisting of a Const and a run-time type coercion (perhaps a FuncExpr or a CoerceViaIO). Modify the raw parse output so that we end up with the original token's location attached to the type coercion node while the Const has location -1; before, it was the other way around. This makes no difference in terms of what exprLocation() will say about the parse tree as a whole, so it should not have any user-visible impact. The point of changing it is that we do not want contrib/pg_stat_statements to treat these constructs as replaceable constants. It will do the right thing if the Const has location -1 rather than a valid location. This is a pretty ugly hack, but then this code is ugly already; we should someday replace this translation with special-purpose parse node(s) that would allow ruleutils.c to reconstruct the original query text. (See also commit 5d3fcc4c2e137417ef470d604fee5e452b22f6a7, which also hacked location assignment rules for the benefit of pg_stat_statements.) Back-patch to 9.2 where pg_stat_statements grew the ability to recognize replaceable constants. Kyotaro Horiguchi
2014-01-11Disallow LATERAL references to the target table of an UPDATE/DELETE.Tom Lane
On second thought, commit 0c051c90082da0b7e5bcaf9aabcbd4f361137cdc was over-hasty: rather than allowing this case, we ought to reject it for now. That leaves the field clear for a future feature that allows the target table to be re-specified in the FROM (or USING) clause, which will enable left-joining the target table to something else. We can then also allow LATERAL references to such an explicitly re-specified target table. But allowing them right now will create ambiguities or worse for such a feature, and it isn't something we documented 9.3 as supporting. While at it, add a convenience subroutine to avoid having several copies of the ereport for disalllowed-LATERAL-reference cases.
2014-01-07Fix LATERAL references to target table of UPDATE/DELETE.Tom Lane
I failed to think much about UPDATE/DELETE when implementing LATERAL :-(. The implemented behavior ended up being that subqueries in the FROM or USING clause (respectively) could access the update/delete target table as though it were a lateral reference; which seems fine if they said LATERAL, but certainly ought to draw an error if they didn't. Fix it so you get a suitable error when you omit LATERAL. Per report from Emre Hasegeli.
2013-12-02Fix crash in assign_collations_walker for EXISTS with empty SELECT list.Tom Lane
We (I think I, actually) forgot about this corner case while coding collation resolution. Per bug #8648 from Arjen Nienhuis.
2013-11-23Fix array slicing of int2vector and oidvector values.Tom Lane
The previous coding labeled expressions such as pg_index.indkey[1:3] as being of int2vector type; which is not right because the subscript bounds of such a result don't, in general, satisfy the restrictions of int2vector. To fix, implicitly promote the result of slicing int2vector to int2[], or oidvector to oid[]. This is similar to what we've done with domains over arrays, which is a good analogy because these types are very much like restricted domains of the corresponding regular-array types. A side-effect is that we now also forbid array-element updates on such columns, eg while "update pg_index set indkey[4] = 42" would have worked before if you were superuser (and corrupted your catalogs irretrievably, no doubt) it's now disallowed. This seems like a good thing since, again, some choices of subscripting would've led to results not satisfying the restrictions of int2vector. The case of an array-slice update was rejected before, though with a different error message than you get now. We could make these cases work in future if we added a cast from int2[] to int2vector (with a cast function checking the subscript restrictions) but it seems unlikely that there's any value in that. Per report from Ronan Dunklau. Back-patch to all supported branches because of the crash risks involved.
2013-11-11Re-allow duplicate aliases within aliased JOINs.Tom Lane
Although the SQL spec forbids duplicate table aliases, historically we've allowed queries like SELECT ... FROM tab1 x CROSS JOIN (tab2 x CROSS JOIN tab3 y) z on the grounds that the aliased join (z) hides the aliases within it, therefore there is no conflict between the two RTEs named "x". The LATERAL patch broke this, on the misguided basis that "x" could be ambiguous if tab3 were a LATERAL subquery. To avoid breaking existing queries, it's better to allow this situation and complain only if tab3 actually does contain an ambiguous reference. We need only remove the check that was throwing an error, because the column lookup code is already prepared to handle ambiguous references. Per bug #8444.
2013-11-06Support default arguments and named-argument notation for window functions.Tom Lane
These things didn't work because the planner omitted to do the necessary preprocessing of a WindowFunc's argument list. Add the few dozen lines of code needed to handle that. Although this sounds like a feature addition, it's really a bug fix because the default-argument case was likely to crash previously, due to lack of checking of the number of supplied arguments in the built-in window functions. It's not a security issue because there's no way for a non-superuser to create a window function definition with defaults that refers to a built-in C function, but nonetheless people might be annoyed that it crashes rather than producing a useful error message. So back-patch as far as the patch applies easily, which turns out to be 9.2. I'll put a band-aid in earlier versions as a separate patch. (Note that these features still don't work for aggregates, and fixing that case will be harder since we represent aggregate arg lists as target lists not bare expression lists. There's no crash risk though because CREATE AGGREGATE doesn't accept defaults, and we reject named-argument notation when parsing an aggregate call.)
2013-11-05Improve the error message given for modifying a window with frame clause.Tom Lane
For rather inscrutable reasons, SQL:2008 disallows copying-and-modifying a window definition that has any explicit framing clause. The error message we gave for this only made sense if the referencing window definition itself contains an explicit framing clause, which it might well not. Moreover, in the context of an OVER clause it's not exactly obvious that "OVER (windowname)" implies copy-and-modify while "OVER windowname" does not. This has led to multiple complaints, eg bug #5199 from Iliya Krapchatov. Change to a hopefully more intelligible error message, and in the case where we have just "OVER (windowname)", add a HINT suggesting that omitting the parentheses will fix it. Also improve the related documentation. Back-patch to all supported branches.
2013-08-07Message style improvementsPeter Eisentraut
2013-08-02Fix crash in error report of invalid tuple lockAlvaro Herrera
My tweak of these error messages in commit c359a1b082 contained the thinko that a query would always have rowMarks set for a query containing a locking clause. Not so: when declaring a cursor, for instance, rowMarks isn't set at the point we're checking, so we'd be dereferencing a NULL pointer. The fix is to pass the lock strength to the function raising the error, instead of trying to reverse-engineer it. The result not only is more robust, but it also seems cleaner overall. Per report from Robert Haas.
2013-07-23Change post-rewriter representation of dropped columns in joinaliasvars.Tom Lane
It's possible to drop a column from an input table of a JOIN clause in a view, if that column is nowhere actually referenced in the view. But it will still be there in the JOIN clause's joinaliasvars list. We used to replace such entries with NULL Const nodes, which is handy for generation of RowExpr expansion of a whole-row reference to the view. The trouble with that is that it can't be distinguished from the situation after subquery pull-up of a constant subquery output expression below the JOIN. Instead, replace such joinaliasvars with null pointers (empty expression trees), which can't be confused with pulled-up expressions. expandRTE() still emits the old convention, though, for convenience of RowExpr generation and to reduce the risk of breaking extension code. In HEAD and 9.3, this patch also fixes a problem with some new code in ruleutils.c that was failing to cope with implicitly-casted joinaliasvars entries, as per recent report from Feike Steenbergen. That oversight was because of an inadequate description of the data structure in parsenodes.h, which I've now corrected. There were some pre-existing oversights of the same ilk elsewhere, which I believe are now all fixed.
2013-07-23Tweak FOR UPDATE/SHARE error message wording (again)Alvaro Herrera
In commit 0ac5ad5134 I changed some error messages from "FOR UPDATE/SHARE" to a rather long gobbledygook which nobody liked. Then, in commit cb9b66d31 I changed them again, but the alternative chosen there was deemed suboptimal by Peter Eisentraut, who in message 1373937980.20441.8.camel@vanquo.pezone.net proposed an alternative involving a dynamically-constructed string based on the actual locking strength specified in the SQL command. This patch implements that suggestion.
2013-07-05Update messages, comments and documentation for materialized views.Noah Misch
All instances of the verbiage lagging the code. Back-patch to 9.3, where materialized views were introduced.
2013-06-09Remove unnecessary restrictions about RowExprs in transformAExprIn().Tom Lane
When the existing code here was written, it made sense to special-case RowExprs because that was the only way that we could handle row comparisons at all. Now that we have record_eq() and arrays of composites, the generic logic for "scalar" types will in fact work on RowExprs too, so there's no reason to throw error for combinations of RowExprs and other ways of forming composite values, nor to ignore the possibility of using a ScalarArrayOpExpr. But keep using the old logic when comparing two RowExprs, for consistency with the main transformAExprOp() logic. (This allows some cases with not-quite-identical rowtypes to succeed, so we might get push-back if we removed it.) Per bug #8198 from Rafal Rzepecki. Back-patch to all supported branches, since this works fine as far back as 8.4. Rafal Rzepecki and Tom Lane
2013-06-08Don't downcase non-ascii identifier chars in multi-byte encodings.Andrew Dunstan
Long-standing code has called tolower() on identifier character bytes with the high bit set. This is clearly an error and produces junk output when the encoding is multi-byte. This patch therefore restricts this activity to cases where there is a character with the high bit set AND the encoding is single-byte. There have been numerous gripes about this, most recently from Martin Schäfer. Backpatch to all live releases.
2013-06-05Put analyze_keyword back in explain_option_name production.Tom Lane
In commit 2c92edad48796119c83d7dbe6c33425d1924626d, I broke "EXPLAIN (ANALYZE)" syntax, because I mistakenly thought that ANALYZE/ANALYSE were only partially reserved and thus would be included in NonReservedWord; but actually they're fully reserved so they still need to be called out here. A nicer solution would be to demote these words to type_func_name_keyword status (they can't be less than that because of "VACUUM [ANALYZE] ColId"). While that works fine so far as the core grammar is concerned, it breaks ECPG's grammar for reasons I don't have time to isolate at the moment. So do this for the time being. Per report from Kevin Grittner. Back-patch to 9.0, like the previous commit.
2013-06-02Allow type_func_name_keywords in some places where they weren't before.Tom Lane
This change makes type_func_name_keywords less reserved than they were before, by allowing them for role names, language names, EXPLAIN and COPY options, and SET values for GUCs; which are all places where few if any actual keywords could appear instead, so no new ambiguities are introduced. The main driver for this change is to allow "COPY ... (FORMAT BINARY)" to work without quoting the word "binary". That is an inconsistency that has been complained of repeatedly over the years (at least by Pavel Golub, Kurt Lidl, and Simon Riggs); but we hadn't thought of any non-ugly solution until now. Back-patch to 9.0 where the COPY (FORMAT BINARY) syntax was introduced.
2013-05-29pgindent run for release 9.3Bruce Momjian
This is the first run of the Perl-based pgindent script. Also update pgindent instructions.
2013-05-06Disallow unlogged materialized views.Tom Lane
The initial implementation of this feature was really unsupportable, because it's relying on the physical size of an on-disk file to carry the relation's populated/unpopulated state, which is at least a modularity violation and could have serious long-term consequences. We could say that an unlogged matview goes to empty on crash, but not everybody likes that definition, so let's just remove the feature for 9.3. We can add it back when we have a less klugy implementation. I left the grammar and tab-completion support for CREATE UNLOGGED MATERIALIZED VIEW in place, since it's harmless and allows delivering a more specific error message about the unsupported feature. I'm committing this separately to ease identification of what should be reverted when/if we are able to re-enable the feature.
2013-04-27Incidental cleanup of matviews code.Tom Lane
Move checking for unscannable matviews into ExecOpenScanRelation, which is a better place for it first because the open relation is already available (saving a relcache lookup cycle), and second because this eliminates the problem of telling the difference between rangetable entries that will or will not be scanned by the query. In particular we can get rid of the not-terribly-well-thought-out-or-implemented isResultRel field that the initial matviews patch added to RangeTblEntry. Also get rid of entirely unnecessary scannability check in the rewriter, and a bogus decision about whether RefreshMatViewStmt requires a parse-time snapshot. catversion bump due to removal of a RangeTblEntry field, which changes stored rules.
2013-04-26Fix collation assignment for aggregates with ORDER BY.Tom Lane
ORDER BY expressions were being treated the same as regular aggregate arguments for purposes of collation determination, but really they should not affect the aggregate's collation at all; only collations of the aggregate's regular arguments should affect it. In many cases this mistake would lead to incorrectly throwing a "collation conflict" error; but in some cases the corrected code will silently assign a different collation to the aggregate than before, for example agg(foo ORDER BY bar COLLATE "x") which will now use foo's collation rather than "x" for the aggregate. Given this risk and the lack of field complaints about the issue, it doesn't seem prudent to back-patch. In passing, rearrange code in assign_collations_walker so that we don't need multiple copies of the standard logic for computing collation of a node with children. (Previously, CaseExpr duplicated the standard logic, and we would have needed a third copy for Aggref without this change.) Andrew Gierth and David Fetter
2013-04-20Clean up references to SQL92Peter Eisentraut
In most cases, these were just references to the SQL standard in general. In a few cases, a contrast was made between SQL92 and later standards -- those have been kept unchanged.
2013-04-12Clean up the mess around EXPLAIN and materialized views.Tom Lane
Revert the matview-related changes in explain.c's API, as per recent complaint from Robert Haas. The reason for these appears to have been principally some ill-considered choices around having intorel_startup do what ought to be parse-time checking, plus a poor arrangement for passing it the view parsetree it needs to store into pg_rewrite when creating a materialized view. Do the latter by having parse analysis stick a copy into the IntoClause, instead of doing it at runtime. (On the whole, I seriously question the choice to represent CREATE MATERIALIZED VIEW as a variant of SELECT INTO/CREATE TABLE AS, because that means injecting even more complexity into what was already a horrid legacy kluge. However, I didn't go so far as to rethink that choice ... yet.) I also moved several error checks into matview parse analysis, and made the check for external Params in a matview more accurate. In passing, clean things up a bit more around interpretOidsOption(), and fix things so that we can use that to force no-oids for views, sequences, etc, thereby eliminating the need to cons up "oids = false" options when creating them. catversion bump due to change in IntoClause. (I wonder though if we really need readfuncs/outfuncs support for IntoClause anymore.)
2013-03-28Add sql_drop event for event triggersAlvaro Herrera
This event takes place just before ddl_command_end, and is fired if and only if at least one object has been dropped by the command. (For instance, DROP TABLE IF EXISTS of a table that does not in fact exist will not lead to such a trigger firing). Commands that drop multiple objects (such as DROP SCHEMA or DROP OWNED BY) will cause a single event to fire. Some firings might be surprising, such as ALTER TABLE DROP COLUMN. The trigger is fired after the drop has taken place, because that has been deemed the safest design, to avoid exposing possibly-inconsistent internal state (system catalogs as well as current transaction) to the user function code. This means that careful tracking of object identification is required during the object removal phase. Like other currently existing events, there is support for tag filtering. To support the new event, add a new pg_event_trigger_dropped_objects() set-returning function, which returns a set of rows comprising the objects affected by the command. This is to be used within the user function code, and is mostly modelled after the recently introduced pg_identify_object() function. Catalog version bumped due to the new function. Dimitri Fontaine and Álvaro Herrera Review by Robert Haas, Tom Lane
2013-03-22Fix problems with incomplete attempt to prohibit OIDS with MVs.Kevin Grittner
Problem with assertion failure in restoring from pg_dump output reported by Joachim Wieland. Review and suggestions by Tom Lane and Robert Haas.
2013-03-20Allow extracting machine-readable object identityAlvaro Herrera
Introduce pg_identify_object(oid,oid,int4), which is similar in spirit to pg_describe_object but instead produces a row of machine-readable information to uniquely identify the given object, without resorting to OIDs or other internal representation. This is intended to be used in the event trigger implementation, to report objects being operated on; but it has usefulness of its own. Catalog version bumped because of the new function.
2013-03-14Change the way UESCAPE is lexed, to reduce the size of the flex tables.Heikki Linnakangas
The error rule used to avoid backtracking with the U&'...' UESCAPE 'x' syntax bloated the flex tables, so refactor that. This patch makes the error rule shorter, by introducing a new exclusive flex state that's entered after parsing U&'...'. This shrinks the postgres binary by about 220kB.
2013-03-12Allow default expressions to be attached to columns of foreign tables.Tom Lane
There's still some discussion about exactly how postgres_fdw ought to handle this case, but there seems no debate that we want to allow defaults to be used for inserts into foreign tables. So remove the core-code restrictions that prevented it. While at it, get rid of the special grammar productions for CREATE FOREIGN TABLE, and instead add explicit FEATURE_NOT_SUPPORTED error checks for the disallowed cases. This makes the grammar a shade smaller, and more importantly results in much more intelligible error messages for unsupported cases. It's also one less thing to fix if we ever start supporting constraints on foreign tables.
2013-03-10Support writable foreign tables.Tom Lane
This patch adds the core-system infrastructure needed to support updates on foreign tables, and extends contrib/postgres_fdw to allow updates against remote Postgres servers. There's still a great deal of room for improvement in optimization of remote updates, but at least there's basic functionality there now. KaiGai Kohei, reviewed by Alexander Korotkov and Laurenz Albe, and rather heavily revised by Tom Lane.
2013-03-03Add a materialized view relations.Kevin Grittner
A materialized view has a rule just like a view and a heap and other physical properties like a table. The rule is only used to populate the table, references in queries refer to the materialized data. This is a minimal implementation, but should still be useful in many cases. Currently data is only populated "on demand" by the CREATE MATERIALIZED VIEW and REFRESH MATERIALIZED VIEW statements. It is expected that future releases will add incremental updates with various timings, and that a more refined concept of defining what is "fresh" data will be developed. At some point it may even be possible to have queries use a materialized in place of references to underlying tables, but that requires the other above-mentioned features to be working first. Much of the documentation work by Robert Haas. Review by Noah Misch, Thom Brown, Robert Haas, Marko Tiikkaja Security review by KaiGai Kohei, with a decision on how best to implement sepgsql still pending.
2013-02-27Add support for piping COPY to/from an external program.Heikki Linnakangas
This includes backend "COPY TO/FROM PROGRAM '...'" syntax, and corresponding psql \copy syntax. Like with reading/writing files, the backend version is superuser-only, and in the psql version, the program is run in the client. In the passing, the psql \copy STDIN/STDOUT syntax is subtly changed: if you the stdin/stdout is quoted, it's now interpreted as a filename. For example, "\copy foo from 'stdin'" now reads from a file called 'stdin', not from standard input. Before this, there was no way to specify a filename called stdin, stdout, pstdin or pstdout. This creates a new function in pgport, wait_result_to_str(), which can be used to convert the exit status of a process, as returned by wait(3), to a human-readable string. Etsuro Fujita, reviewed by Amit Kapila.
2013-02-17Add ALTER ROLE ALL SET commandPeter Eisentraut
This generalizes the existing ALTER ROLE ... SET and ALTER DATABASE ... SET functionality to allow creating settings that apply to all users in all databases. reviewed by Pavel Stehule
2013-02-08Add support for ALTER RULE ... RENAME TO.Tom Lane
Ali Dar, reviewed by Dean Rasheed.
2013-02-06Improve error message wordingAlvaro Herrera
The wording changes applied in 0ac5ad513 were universally disliked. Per gripe from Andrew Dunstan
2013-01-31Add CREATE RECURSIVE VIEW syntaxPeter Eisentraut
This is specified in the SQL standard. The CREATE RECURSIVE VIEW specification is transformed into a normal CREATE VIEW statement with a WITH RECURSIVE clause. reviewed by Abhijit Menon-Sen and Stephen Frost
2013-01-30Fix grammar for subscripting or field selection from a sub-SELECT result.Tom Lane
Such cases should work, but the grammar failed to accept them because of our ancient precedence hacks to convince bison that extra parentheses around a sub-SELECT in an expression are unambiguous. (Formally, they *are* ambiguous, but we don't especially care whether they're treated as part of the sub-SELECT or part of the expression. Bison cares, though.) Fix by adding a redundant-looking production for this case. This is a fine example of why fixing shift/reduce conflicts via precedence declarations is more dangerous than it looks: you can easily cause the parser to reject cases that should work. This has been wrong since commit 3db4056e22b0c6b2adc92543baf8408d2894fe91 or maybe before, and apparently some people have been working around it by inserting no-op casts. That method introduces a dump/reload hazard, as illustrated in bug #7838 from Jan Mate. Hence, back-patch to all active branches.
2013-01-26Make LATERAL implicit for functions in FROM.Tom Lane
The SQL standard does not have general functions-in-FROM, but it does allow UNNEST() there (see the <collection derived table> production), and the semantics of that are defined to include lateral references. So spec compliance requires allowing lateral references within UNNEST() even without an explicit LATERAL keyword. Rather than making UNNEST() a special case, it seems best to extend this flexibility to any function-in-FROM. We'll still allow LATERAL to be written explicitly for clarity's sake, but it's now a noise word in this context. In theory this change could result in a change in behavior of existing queries, by allowing what had been an outer reference in a function-in-FROM to be captured by an earlier FROM-item at the same level. However, all pre-9.3 PG releases have a bug that causes them to match variable references to earlier FROM-items in preference to outer references (and then throw an error). So no previously-working query could contain the type of ambiguity that would risk a change of behavior. Per a suggestion from Andrew Gierth, though I didn't use his patch.