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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
2014-02-13Fix 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.
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.
2013-11-05Improve 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.
2013-07-23Change 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.
2013-06-09Remove 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.
2013-01-30Fix 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.
2012-12-23Prevent failure when RowExpr or XmlExpr is parse-analyzed twice.Tom Lane
transformExpr() is required to cope with already-transformed expression trees, for various ugly-but-not-quite-worth-cleaning-up reasons. However, some of its newer subroutines hadn't gotten the memo. This accounts for bug #7763 from Norbert Buchmuller: transformRowExpr() was overwriting the previously determined type of a RowExpr during CREATE TABLE LIKE INCLUDING INDEXES. Additional investigation showed that transformXmlExpr had the same kind of problem, but all the other cases seem to be safe. Andres Freund and Tom Lane
2012-11-11Check for stack overflow in transformSetOperationTree().Tom Lane
Since transformSetOperationTree() recurses, it can be driven to stack overflow with enough UNION/INTERSECT/EXCEPT clauses in a query. Add a check to ensure it fails cleanly instead of crashing. Per report from Matthew Gerber (though it's not clear whether this is the only thing going wrong for him). Historical note: I think the reasoning behind not putting a check here in the beginning was that the check in transformExpr() ought to be sufficient to guard the whole parser. However, because transformSetOperationTree() recurses all the way to the bottom of the set-operation tree before doing any analysis of the statement's expressions, that check doesn't save it.
2012-10-24Prevent parser from believing that views have system columns.Tom Lane
Views should not have any pg_attribute entries for system columns. However, we forgot to remove such entries when converting a table to a view. This could lead to crashes later on, if someone attempted to reference such a column, as reported by Kohei KaiGai. This problem is corrected properly in HEAD (by removing the pg_attribute entries during conversion), but in the back branches we need to defend against existing mis-converted views. This fix costs us an extra syscache lookup per system column reference, which is annoying but probably not really measurable in the big scheme of things.
2012-07-31Fix WITH attached to a nested set operation (UNION/INTERSECT/EXCEPT).Tom Lane
Parse analysis neglected to cover the case of a WITH clause attached to an intermediate-level set operation; it only handled WITH at the top level or WITH attached to a leaf-level SELECT. Per report from Adam Mackler. In HEAD, I rearranged the order of SelectStmt's fields to put withClause with the other fields that can appear on non-leaf SelectStmts. In back branches, leave it alone to avoid a possible ABI break for third-party code. Back-patch to 8.4 where WITH support was added.
2012-06-30Prevent CREATE TABLE LIKE/INHERITS from (mis) copying whole-row Vars.Tom Lane
If a CHECK constraint or index definition contained a whole-row Var (that is, "table.*"), an attempt to copy that definition via CREATE TABLE LIKE or table inheritance produced incorrect results: the copied Var still claimed to have the rowtype of the source table, rather than the created table. For the LIKE case, it seems reasonable to just throw error for this situation, since the point of LIKE is that the new table is not permanently coupled to the old, so there's no reason to assume its rowtype will stay compatible. In the inheritance case, we should ideally allow such constraints, but doing so will require nontrivial refactoring of CREATE TABLE processing (because we'd need to know the OID of the new table's rowtype before we adjust inherited CHECK constraints). In view of the lack of previous complaints, that doesn't seem worth the risk in a back-patched bug fix, so just make it throw error for the inheritance case as well. Along the way, replace change_varattnos_of_a_node() with a more robust function map_variable_attnos(), which is capable of being extended to handle insertion of ConvertRowtypeExpr whenever we get around to fixing the inheritance case nicely, and in the meantime it returns a failure indication to the caller so that a helpful message with some context can be thrown. Also, this code will do the right thing with subselects (if we ever allow them in CHECK or indexes), and it range-checks varattnos before using them to index into the map array. Per report from Sergey Konoplev. Back-patch to all supported branches.
2011-10-08Don't let transform_null_equals=on affect CASE foo WHEN NULL ... constructs.Heikki Linnakangas
transform_null_equals is only supposed to affect "foo = NULL" expressions given directly by the user, not the internal "foo = NULL" expression generated from CASE-WHEN. This fixes bug #6242, reported by Sergey. Backpatch to all supported branches.
2011-06-04Expose the "*VALUES*" alias that we generate for a stand-alone VALUES list.Tom Lane
We were trying to make that strictly an internal implementation detail, but it turns out that it's exposed anyway when dumping a view defined like CREATE VIEW test_view AS VALUES (1), (2), (3) ORDER BY 1; This comes out as CREATE VIEW ... ORDER BY "*VALUES*".column1; which fails to parse when reloading the dump. Hacking ruleutils.c to suppress the column qualification looks like it'd be a risky business, so instead promote the RTE alias to full-fledged usability. Per bug #6049 from Dylan Adams. Back-patch to all supported branches.
2010-10-02Behave correctly if INSERT ... VALUES is decorated with additional clauses.Tom Lane
In versions 8.2 and up, the grammar allows attaching ORDER BY, LIMIT, FOR UPDATE, or WITH to VALUES, and hence to INSERT ... VALUES. But the special-case code for VALUES in transformInsertStmt() wasn't expecting any of those, and just ignored them, leading to unexpected results. Rather than complicate the special-case path, just ensure that the presence of any of those clauses makes us treat the query as if it had a general SELECT. Per report from Hitoshi Harada.
2010-09-25Further fixes to the pg_get_expr() security fix in back branches.Tom Lane
It now emerges that the JDBC driver expects to be able to use pg_get_expr() on an output of a sub-SELECT. So extend the check logic to be able to recurse into a sub-SELECT to see if the argument is ultimately coming from an appropriate column. Per report from Thomas Kellerer.
2010-09-22Convert cvsignore to gitignore, and add .gitignore for build targets.Magnus Hagander
2010-07-30Improved version of patch to protect pg_get_expr() against misuse:Tom Lane
look through join alias Vars to avoid breaking join queries, and move the test to someplace where it will catch more possible ways of calling a function. We still ought to throw away the whole thing in favor of a data-type-based solution, but that's not feasible in the back branches. Completion of back-port of my patch of yesterday.
2010-06-30stringToNode() and deparse_expression_pretty() crash on invalid input,Heikki Linnakangas
but we have nevertheless exposed them to users via pg_get_expr(). It would be too much maintenance effort to rigorously check the input, so put a hack in place instead to restrict pg_get_expr() so that the argument must come from one of the system catalog columns known to contain valid expressions. Per report from Rushabh Lathia. Backpatch to 7.4 which is the oldest supported version at the moment.
2010-05-08Work around a subtle portability problem in use of printf %s format.Tom Lane
Depending on which spec you read, field widths and precisions in %s may be counted either in bytes or characters. Our code was assuming bytes, which is wrong at least for glibc's implementation, and in any case libc might have a different idea of the prevailing encoding than we do. Hence, for portable results we must avoid using anything more complex than just "%s" unless the string to be printed is known to be all-ASCII. This patch fixes the cases I could find, including the psql formatting failure reported by Hernan Gonzalez. In HEAD only, I also added comments to some places where it appears safe to continue using "%.*s".
2010-03-04Fix IsBinaryCoercible to not confuse a cast using in/out functionsHeikki Linnakangas
with binary compatibility. Backpatch to 8.4 where INOUT casts were introduced.
2009-12-16Avoid a premature coercion failure in transformSetOperationTree() whenTom Lane
presented with an UNKNOWN-type Var, which can happen in cases where an unknown literal appeared in a subquery. While many such cases will fail later on anyway in the planner, there are some cases where the planner is able to flatten the query and replace the Var by the constant before it has to coerce the union column to the final type. I had added this check in 8.4 to provide earlier/better error detection, but it causes a regression for some cases that worked OK before. Fix by not making the check if the input node is UNKNOWN type and not a Const or Param. If it isn't going to work, it will fail anyway at plan time, with the only real loss being inability to provide an error cursor. Per gripe from Britt Piehler. In passing, rename a couple of variables to remove confusion from an inner scope masking the same variable names in an outer scope.
2009-11-13A better fix for the "ARRAY[...]::domain" problem. The previous patch worked,Heikki Linnakangas
but the transformed ArrayExpr claimed to have a return type of "domain", even though the domain constraint was only checked by the enclosing CoerceToDomain node. With this fix, the ArrayExpr is correctly labeled with the base type of the domain. Per gripe by Tom Lane.
2009-11-13When you do "ARRAY[...]::domain", where domain is a domain over an array type,Heikki Linnakangas
we need to check domain constraints. We used to do it correctly, but 8.4 introduced a separate code path for the "ARRAY[]::arraytype" case to infer the type of an empty ARRAY construct from the cast target, and forgot to take domains into account. Per report from Florian G. Pflug.
2009-10-27Make FOR UPDATE/SHARE in the primary query not propagate into WITH queries;Tom Lane
for example in WITH w AS (SELECT * FROM foo) SELECT * FROM w, bar ... FOR UPDATE the FOR UPDATE will now affect bar but not foo. This is more useful and consistent than the original 8.4 behavior, which tried to propagate FOR UPDATE into the WITH query but always failed due to assorted implementation restrictions. Even though we are in process of removing those restrictions, it seems correct on philosophical grounds to not let the outer query's FOR UPDATE affect the WITH query. In passing, fix isLockedRel which frequently got things wrong in nested-subquery cases: "FOR UPDATE OF foo" applies to an alias foo in the current query level, not subqueries. This has been broken for a long time, but it doesn't seem worth back-patching further than 8.4 because the actual consequences are minimal. At worst the parser would sometimes get RowShareLock on a relation when it should be AccessShareLock or vice versa. That would only make a difference if someone were using ExclusiveLock concurrently, which no standard operation does, and anyway FOR UPDATE doesn't result in visible changes so it's not clear that the someone would notice any problem. Between that and the fact that FOR UPDATE barely works with subqueries at all in existing releases, I'm not excited about worrying about it.
2009-10-06Change CREATE TABLE so that column default expressions coming from differentTom Lane
inheritance parent tables are compared using equal(), instead of doing strcmp() on the nodeToString representation. The old implementation was always a tad cheesy, and it finally fails completely as of 8.4, now that the node tree might contain syntax location information. equal() knows it's supposed to ignore those fields, but strcmp() hardly can. Per recent report from Scott Ribe.
2009-09-09Fix bug with WITH RECURSIVE immediately inside WITH RECURSIVE. 99% of theTom Lane
code was already okay with this, but the hack that obtained the output column types of a recursive union in advance of doing real parse analysis of the recursive union forgot to handle the case where there was an inner WITH clause available to the non-recursive term. Best fix seems to be to refactor so that we don't need the "throwaway" parse analysis step at all. Instead, teach the transformSetOperationStmt code to set up the CTE's output column information after it's processed the non-recursive term normally. Per report from David Fetter.
2009-08-27Modify the definition of window-function PARTITION BY and ORDER BY clausesTom Lane
so that their elements are always taken as simple expressions over the query's input columns. It originally seemed like a good idea to make them act exactly like GROUP BY and ORDER BY, right down to the SQL92-era behavior of accepting output column names or numbers. However, that was not such a great idea, for two reasons: 1. It permits circular references, as exhibited in bug #5018: the output column could be the one containing the window function itself. (We actually had a regression test case illustrating this, but nobody thought twice about how confusing that would be.) 2. It doesn't seem like a good idea for, eg, "lead(foo) OVER (ORDER BY foo)" to potentially use two completely different meanings for "foo". Accordingly, narrow down the behavior of window clauses to use only the SQL99-compliant interpretation that the expressions are simple expressions.
2009-07-06Per SQL spec (in particular, the grammar in SQL:2008 7.13) we should allowTom Lane
parentheses around the <query expression body> that follows a WITH clause, eg with cte(foo) as ( values(0) ) ((select foo from cte)); This seems to be just an oversight/thinko in gram.y. Noted while experimenting with bug #4902.
2009-06-18Fix the just-reported problem that you can't specify all four trigger eventTom Lane
types in CREATE TRIGGER. While at it, clean up the amazingly tedious and inextensible way that the trigger event type list was handled. Per report from Greg Sabino Mullane.
2009-06-13Fix get_sort_group_operators() so that it doesn't think arrays can be groupedTom Lane
via hashing. Eventually we ought to make that possible, but it won't happen for 8.4. Per yesterday's report from Robert Haas.
2009-06-118.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef listBruce Momjian
provided by Andrew.
2009-06-04Improve the recently-added support for properly pluralized error messagesTom Lane
by extending the ereport() API to cater for pluralization directly. This is better than the original method of calling ngettext outside the elog.c code because (1) it avoids double translation, which wastes cycles and in the worst case could give a wrong result; and (2) it avoids having to use a different coding method in PL code than in the core backend. The client-side uses of ngettext are not touched since neither of these concerns is very pressing in the client environment. Per my proposal of yesterday.
2009-05-27Ignore RECHECK in CREATE OPERATOR CLASS, just throwing a NOTICE, instead ofTom Lane
throwing an error as 8.4 had been doing. The error interfered with porting old database definitions (particularly for pg_migrator) without really buying any safety. Per bug #4817 and subsequent discussion.
2009-05-12Modify find_inheritance_children() and find_all_inheritors() to add theTom Lane
ability to lock relations as they scan pg_inherits, and to ignore any relations that have disappeared by the time we get lock on them. This makes uses of these functions safe against concurrent DROP operations on child tables: we will effectively ignore any just-dropped child, rather than possibly throwing an error as in recent bug report from Thomas Johansson (and similar past complaints). The behavior should not change otherwise, since the code was acquiring those same locks anyway, just a little bit later. An exception is LockTableCommand(), which is still behaving unsafely; but that seems to require some more discussion before we change it.
2009-05-12Do some minor code refactoring in preparation for changing the APIs ofTom Lane
find_inheritance_children() and find_all_inheritors(). I got annoyed that these are buried inside the planner but mostly used elsewhere. So, create a new file catalog/pg_inherits.c and put them there, along with a couple of other functions that search pg_inherits. The code that modifies pg_inherits is (still) in tablecmds.c --- it's kind of entangled with unrelated code that modifies pg_depend and other stuff, so pulling it out seemed like a bigger change than I wanted to make right now. But this file provides a natural home for it if anyone ever gets around to that. This commit just moves code around; it doesn't change anything, except I succumbed to the temptation to make a couple of trivial optimizations in typeInheritsFrom().
2009-05-05Make new complaint about unsafe Unicode literals include an error location.Tom Lane
Every other ereport in scan.l has one, this should too.
2009-05-05Disable the use of Unicode escapes in string constants (U&'') whenPeter Eisentraut
standard_conforming_strings is not on, for security reasons.
2009-04-28Move SERVER to the right place in the alphabetically sorted keyword list.Heikki Linnakangas
2009-04-24Fix some more 'variable may be used uninitialized' warnings from gcc 4.4.Tom Lane
2009-04-19Rethink the idea of having plpgsql depend on parser/gram.h. Aside from theTom Lane
fact that this is breaking the MSVC build, it's probably not really a good idea to expand the dependencies of gram.h any further than the core parser; for instance the value of SCONST might depend on which bison version you'd built with. Better to expose an additional call point in parser.c, so move what I had put into pl_funcs.c into parser.c. Also PGDLLIMPORT'ify the reference to standard_conforming_strings, per buildfarm results.
2009-04-19Fix de-escaping checks so that we will reject \000 as well as other invalidlyTom Lane
encoded sequences. Per discussion of a couple of days ago.
2009-04-14Fix broken {xufailed} production that made HEAD fail onTom Lane
select u&42 from table-with-a-u-column; Also fix missing SET_YYLLOC() in the {dolqfailed} production that I suppose this was based on. The latter is a pre-existing bug, but the only effect is to misplace the error cursor by one token, so probably not worth backpatching.
2009-04-06Rename the new CREATE DATABASE options to set collation and ctype intoHeikki Linnakangas
LC_COLLATE and LC_CTYPE, per discussion on pgsql-hackers.
2009-04-04Remove the recently added node types ReloptElem and OptionDefElem in favorTom Lane
of adding optional namespace and action fields to DefElem. Having three node types that do essentially the same thing bloats the code and leads to errors of confusion, such as in yesterday's bug report from Khee Chin.
2009-03-26Gettext plural supportPeter Eisentraut
In the backend, I changed only a handful of exemplary or important-looking instances to make use of the plural support; there is probably more work there. For the rest of the source, this should cover all relevant cases.
2009-03-08Add comments about kwlookup.c expectationsAlvaro Herrera
2009-03-07Separate the key word list that lived in keywords.c into a new header fileAlvaro Herrera
kwlist.h, to avoid having to link the backend object file into other programs like pg_dump. We can now simply symlink a single source file from the backend (kwlookup.c, containing the shared routine ScanKeywordLookup) and compile it locally, which is a lot cleaner.