611 Commits (b1ffe3ff0b7ed87b34ae0fc6eba71bf032e41b59)

Author	SHA1	Message	Date
Peter Eisentraut	7c4f52409a	Logical replication support for initial data copy ... Add functionality for a new subscription to copy the initial data in the tables and then sync with the ongoing apply process. For the copying, add a new internal COPY option to have the COPY source data provided by a callback function. The initial data copy works on the subscriber by receiving COPY data from the publisher and then providing it locally into a COPY that writes to the destination table. A WAL receiver can now execute full SQL commands. This is used here to obtain information about tables and publications. Several new options were added to CREATE and ALTER SUBSCRIPTION to control whether and when initial table syncing happens. Change pg_dump option --no-create-subscription-slots to --no-subscription-connect and use the new CREATE SUBSCRIPTION ... NOCONNECT option for that. Author: Petr Jelinek <petr.jelinek@2ndquadrant.com> Tested-by: Erik Rijkers <er@xs4all.nl>	9 years ago
Alvaro Herrera	fcec6caafa	Support XMLTABLE query expression ... XMLTABLE is defined by the SQL/XML standard as a feature that allows turning XML-formatted data into relational form, so that it can be used as a <table primary> in the FROM clause of a query. This new construct provides significant simplicity and performance benefit for XML data processing; what in a client-side custom implementation was reported to take 20 minutes can be executed in 400ms using XMLTABLE. (The same functionality was said to take 10 seconds using nested PostgreSQL XPath function calls, and 5 seconds using XMLReader under PL/Python). The implemented syntax deviates slightly from what the standard requires. First, the standard indicates that the PASSING clause is optional and that multiple XML input documents may be given to it; we make it mandatory and accept a single document only. Second, we don't currently support a default namespace to be specified. This implementation relies on a new executor node based on a hardcoded method table. (Because the grammar is fixed, there is no extensibility in the current approach; further constructs can be implemented on top of this such as JSON_TABLE, but they require changes to core code.) Author: Pavel Stehule, Álvaro Herrera Extensively reviewed by: Craig Ringer Discussion: https://postgr.es/m/CAFj8pRAgfzMD-LoSmnMGybD0WsEznLHWap8DO79+-GTRAPR4qA@mail.gmail.com	9 years ago
Peter Eisentraut	2ca64c6f71	Replace LookupFuncNameTypeNames() with LookupFuncWithArgs() ... The old function took function name and function argument list as separate arguments. Now that all function signatures are passed around as ObjectWithArgs structs, this is no longer necessary and can be replaced by a function that takes ObjectWithArgs directly. Similarly for aggregates and operators. Reviewed-by: Jim Nasby <Jim.Nasby@BlueTreble.com> Reviewed-by: Michael Paquier <michael.paquier@gmail.com>	9 years ago
Tom Lane	aebeb4790c	Remove vestigial resolveUnknown arguments from transformSortClause etc. ... There's really no situation where we don't want these unknown-to-text conversions to happen. The alternative is failure anyway, and the one caller that was passing "false" did so only because it expected the case could not arise. Might as well simplify the code. Discussion: https://postgr.es/m/CAH2L28uwwbL9HUM-WR=hromW1Cvamkn7O-g8fPY2m=_7muJ0oA@mail.gmail.com	9 years ago
Tom Lane	1e7c4bb004	Change unknown-type literals to type text in SELECT and RETURNING lists. ... Previously, we left such literals alone if the query or subquery had no properties forcing a type decision to be made (such as an ORDER BY or DISTINCT clause using that output column). This meant that "unknown" could be an exposed output column type, which has never been a great idea because it could result in strange failures later on. For example, an outer query that tried to do any operations on an unknown-type subquery output would generally fail with some weird error like "failed to find conversion function from unknown to text" or "could not determine which collation to use for string comparison". Also, if the case occurred in a CREATE VIEW's query then the view would have an unknown-type column, causing similar failures in queries trying to use the view. To fix, at the tail end of parse analysis of a query, forcibly convert any remaining "unknown" literals in its SELECT or RETURNING list to type text. However, provide a switch to suppress that, and use it in the cases of SELECT inside a set operation or INSERT command. In those cases we already had type resolution rules that make use of context information from outside the subquery proper, and we don't want to change that behavior. Also, change creation of an unknown-type column in a relation from a warning to a hard error. The error should be unreachable now in CREATE VIEW or CREATE MATVIEW, but it's still possible to explicitly say "unknown" in CREATE TABLE or CREATE (composite) TYPE. We want to forbid that because it's nothing but a foot-gun. This change creates a pg_upgrade failure case: a matview that contains an unknown-type column can't be pg_upgraded, because reparsing the matview's defining query will now decide that the column is of type text, which doesn't match the cstring-like storage that the old materialized column would actually have. Add a checking pass to detect that. While at it, we can detect tables or composite types that would fail, essentially for free. Those would fail safely anyway later on, but we might as well fail earlier. This patch is by me, but it owes something to previous investigations by Rahila Syed. Also thanks to Ashutosh Bapat and Michael Paquier for review. Discussion: https://postgr.es/m/CAH2L28uwwbL9HUM-WR=hromW1Cvamkn7O-g8fPY2m=_7muJ0oA@mail.gmail.com	9 years ago
Peter Eisentraut	665d1fad99	Logical replication ... - Add PUBLICATION catalogs and DDL - Add SUBSCRIPTION catalog and DDL - Define logical replication protocol and output plugin - Add logical replication workers From: Petr Jelinek <petr@2ndquadrant.com> Reviewed-by: Steve Singer <steve@ssinger.info> Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Erik Rijkers <er@xs4all.nl> Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>	9 years ago
Tom Lane	d43a619c60	Fix check_srf_call_placement() to handle VALUES cases correctly. ... INSERT ... VALUES with a single VALUES row is implemented quite differently from the general VALUES case. A user-visible implication of that is that we accept SRFs in the single-row case, but not in the multi-row case. That's a historical artifact no doubt, but in view of the lack of field complaints, I'm not excited about fixing it right now. However, check_srf_call_placement() needs to know about this, first because it should throw an error in the unsupported case, and second because it should set p_hasTargetSRFs in the single-row case (because we treat that like a SELECT tlist). That's an oversight in commit a4c35ea1c. To fix, split EXPR_KIND_VALUES into two values. So far as I can see, this is the only place where we need to distinguish the two cases at present; but there might be more later. Patch by me, per report from Andres Freund. Discussion: https://postgr.es/m/20170116081548.zg63zltblwimpfgp@alap3.anarazel.de	9 years ago
Tom Lane	ab1f0c8225	Change representation of statement lists, and add statement location info. ... This patch makes several changes that improve the consistency of representation of lists of statements. It's always been the case that the output of parse analysis is a list of Query nodes, whatever the types of the individual statements in the list. This patch brings similar consistency to the outputs of raw parsing and planning steps: * The output of raw parsing is now always a list of RawStmt nodes; the statement-type-dependent nodes are one level down from that. * The output of pg_plan_queries() is now always a list of PlannedStmt nodes, even for utility statements. In the case of a utility statement, "planning" just consists of wrapping a CMD_UTILITY PlannedStmt around the utility node. This list representation is now used in Portal and CachedPlan plan lists, replacing the former convention of intermixing PlannedStmts with bare utility-statement nodes. Now, every list of statements has a consistent head-node type depending on how far along it is in processing. This allows changing many places that formerly used generic "Node *" pointers to use a more specific pointer type, thus reducing the number of IsA() tests and casts needed, as well as improving code clarity. Also, the post-parse-analysis representation of DECLARE CURSOR is changed so that it looks more like EXPLAIN, PREPARE, etc. That is, the contained SELECT remains a child of the DeclareCursorStmt rather than getting flipped around to be the other way. It's now true for both Query and PlannedStmt that utilityStmt is non-null if and only if commandType is CMD_UTILITY. That allows simplifying a lot of places that were testing both fields. (I think some of those were just defensive programming, but in many places, it was actually necessary to avoid confusing DECLARE CURSOR with SELECT.) Because PlannedStmt carries a canSetTag field, we're also able to get rid of some ad-hoc rules about how to reconstruct canSetTag for a bare utility statement; specifically, the assumption that a utility is canSetTag if and only if it's the only one in its list. While I see no near-term need for relaxing that restriction, it's nice to get rid of the ad-hocery. The API of ProcessUtility() is changed so that what it's passed is the wrapper PlannedStmt not just the bare utility statement. This will affect all users of ProcessUtility_hook, but the changes are pretty trivial; see the affected contrib modules for examples of the minimum change needed. (Most compilers should give pointer-type-mismatch warnings for uncorrected code.) There's also a change in the API of ExplainOneQuery_hook, to pass through cursorOptions instead of expecting hook functions to know what to pick. This is needed because of the DECLARE CURSOR changes, but really should have been done in 9.6; it's unlikely that any extant hook functions know about using CURSOR_OPT_PARALLEL_OK. Finally, teach gram.y to save statement boundary locations in RawStmt nodes, and pass those through to Query and PlannedStmt nodes. This allows more intelligent handling of cases where a source query string contains multiple statements. This patch doesn't actually do anything with the information, but a follow-on patch will. (Passing this information through cleanly is the true motivation for these changes; while I think this is all good cleanup, it's unlikely we'd have bothered without this end goal.) catversion bump because addition of location fields to struct Query affects stored rules. This patch is by me, but it owes a good deal to Fabien Coelho who did a lot of preliminary work on the problem, and also reviewed the patch. Discussion: https://postgr.es/m/alpine.DEB.2.20.1612200926310.29821@lancre	9 years ago
Tom Lane	7c3abe3c92	Get rid of ParseState.p_value_substitute; use a columnref hook instead. ... I noticed that p_value_substitute, which is a single-purpose kluge I added in 2002 (commit b0422b215), could be replaced by having domainAddConstraint install a parser hook that looks for the name "value". The parser hook code only dates back to 2009, so it's not surprising that we had to kluge this in 2002, but we can do it more cleanly now.	9 years ago
Tom Lane	3c40594e6e	Improve documentation of struct ParseState. ... I got annoyed about how some fields of ParseState were documented in the struct's block comment and some weren't; not all of the latter are trivial. Fix that. Also reorder a couple of fields that seem to have been placed rather randomly, or maybe with an idea of avoiding padding space; but there are never so many ParseStates in existence at one time that we ought to value pad space over readability.	9 years ago
Bruce Momjian	1d25779284	Update copyright via script for 2017	9 years ago
Robert Haas	e13486eba0	Remove sql_inheritance GUC. ... This backward-compatibility GUC is long overdue for removal. Discussion: http://postgr.es/m/CA+TgmoYe+EG7LdYX6pkcNxr4ygkP4+A=jm9o-CPXyOvRiCNwaQ@mail.gmail.com	9 years ago
Tom Lane	0b78106cd4	Fix reporting of column typmods for multi-row VALUES constructs. ... expandRTE() and get_rte_attribute_type() reported the exprType() and exprTypmod() values of the expressions in the first row of the VALUES as being the column type/typmod returned by the VALUES RTE. That's fine for the data type, since we coerce all expressions in a column to have the same common type. But we don't coerce them to have a common typmod, so it was possible for rows after the first one to return values that violate the claimed column typmod. This leads to the incorrect result seen in bug #14448 from Hassan Mahmood, as well as some other corner-case misbehaviors. The desired behavior is the same as we use in other type-unification cases: report the common typmod if there is one, but otherwise return -1 indicating no particular constraint. It's cheap for transformValuesClause to determine the common typmod while transforming a multi-row VALUES, but it'd be less cheap for expandRTE() and get_rte_attribute_type() to re-determine that info every time they're asked --- possibly a lot less cheap, if the VALUES has many rows. Therefore, the best fix is to record the common typmods explicitly in a list in the VALUES RTE, as we were already doing for column collations. This looks quite a bit like what we're doing for CTE RTEs, so we can save a little bit of space and code by unifying the representation for those two RTE types. They both now share coltypes/coltypmods/colcollations fields. (At some point it might seem desirable to populate those fields for all RTE types; but right now it looks like constructing them for other RTE types would add more code and cycles than it would save.) The RTE change requires a catversion bump, so this fix is only usable in HEAD. If we fix this at all in the back branches, the patch will need to look quite different. Report: https://postgr.es/m/20161205143037.4377.60754@wrigleys.postgresql.org Discussion: https://postgr.es/m/27429.1480968538@sss.pgh.pa.us	9 years ago
Robert Haas	f0e44751d7	Implement table partitioning. ... Table partitioning is like table inheritance and reuses much of the existing infrastructure, but there are some important differences. The parent is called a partitioned table and is always empty; it may not have indexes or non-inherited constraints, since those make no sense for a relation with no data of its own. The children are called partitions and contain all of the actual data. Each partition has an implicit partitioning constraint. Multiple inheritance is not allowed, and partitioning and inheritance can't be mixed. Partitions can't have extra columns and may not allow nulls unless the parent does. Tuples inserted into the parent are automatically routed to the correct partition, so tuple-routing ON INSERT triggers are not needed. Tuple routing isn't yet supported for partitions which are foreign tables, and it doesn't handle updates that cross partition boundaries. Currently, tables can be range-partitioned or list-partitioned. List partitioning is limited to a single column, but range partitioning can involve multiple columns. A partitioning "column" can be an expression. Because table partitioning is less general than table inheritance, it is hoped that it will be easier to reason about properties of partitions, and therefore that this will serve as a better foundation for a variety of possible optimizations, including query planner optimizations. The tuple routing based which this patch does based on the implicit partitioning constraints is an example of this, but it seems likely that many other useful optimizations are also possible. Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat, Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova, Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.	9 years ago
Tom Lane	906bfcad7b	Improve handling of "UPDATE ... SET (column_list) = row_constructor". ... Previously, the right-hand side of a multiple-column assignment, if it wasn't a sub-SELECT, had to be a simple parenthesized expression list, because gram.y was responsible for "bursting" the construct into independent column assignments. This had the minor defect that you couldn't write ROW (though you should be able to, since the standard says this is a row constructor), and the rather larger defect that unlike other uses of row constructors, we would not expand a "foo.*" item into multiple columns. Fix that by changing the RHS to be just "a_expr" in the grammar, leaving it to transformMultiAssignRef to separate the elements of a RowExpr; which it will do only after performing standard transformation of the RowExpr, so that "foo.*" behaves as expected. The key reason we didn't do that before was the hard-wired handling of DEFAULT tokens (SetToDefault nodes). This patch deals with that issue by allowing DEFAULT in any a_expr and having parse analysis throw an error if SetToDefault is found in an unexpected place. That's an improvement anyway since the error can be more specific than just "syntax error". The SQL standard suggests that the RHS could be any a_expr yielding a suitable row value. This patch doesn't really move the goal posts in that respect --- you're still limited to RowExpr or a sub-SELECT --- but it does fix the grammar restriction, so it provides some tangible progress towards a full implementation. And the limitation is now documented by an explicit error message rather than an unhelpful "syntax error". Discussion: <8542.1479742008@sss.pgh.pa.us>	9 years ago
Kevin Grittner	8c48375e5f	Implement syntax for transition tables in AFTER triggers. ... This is infrastructure for the complete SQL standard feature. No support is included at this point for execution nodes or PLs. The intent is to add that soon. As this patch leaves things, standard syntax can create tuplestores to contain old and/or new versions of rows affected by a statement. References to these tuplestores are in the TriggerData structure. C triggers can access the tuplestores directly, so they are usable, but they cannot yet be referenced within a SQL statement.	9 years ago
Tom Lane	a4c35ea1c2	Improve parser's and planner's handling of set-returning functions. ... Teach the parser to reject misplaced set-returning functions during parse analysis using p_expr_kind, in much the same way as we do for aggregates and window functions (cf commit eaccfded9). While this isn't complete (it misses nesting-based restrictions), it's much better than the previous error reporting for such cases, and it allows elimination of assorted ad-hoc expression_returns_set() error checks. We could add nesting checks later if it seems important to catch all cases at parse time. There is one case the parser will now throw error for although previous versions allowed it, which is SRFs in the tlist of an UPDATE. That never behaved sensibly (since it's ill-defined which generated row should be used to perform the update) and it's hard to see why it should not be treated as an error. It's a release-note-worthy change though. Also, add a new Query field hasTargetSRFs reporting whether there are any SRFs in the targetlist (including GROUP BY/ORDER BY expressions). The parser can now set that basically for free during parse analysis, and we can use it in a number of places to avoid expression_returns_set searches. (There will be more such checks soon.) In some places, this allows decontorting the logic since it's no longer expensive to check for SRFs in the tlist --- so I made the checks parallel to the handling of hasAggs/hasWindowFuncs wherever it seemed appropriate. catversion bump because adding a Query field changes stored rules. Andres Freund and Tom Lane Discussion: <24639.1473782855@sss.pgh.pa.us>	9 years ago
Tom Lane	f8ace5477e	Fix type-safety problem with parallel aggregate serial/deserialization. ... The original specification for this called for the deserialization function to have signature "deserialize(serialtype) returns transtype", which is a security violation if transtype is INTERNAL (which it always would be in practice) and serialtype is not (which ditto). The patch blithely overrode the opr_sanity check for that, which was sloppy-enough work in itself, but the indisputable reason this cannot be allowed to stand is that CREATE FUNCTION will reject such a signature and thus it'd be impossible for extensions to create parallelizable aggregates. The minimum fix to make the signature type-safe is to add a second, dummy argument of type INTERNAL. But to lock it down a bit more and make misuse of INTERNAL-accepting functions less likely, let's get rid of the ability to specify a "serialtype" for an aggregate and just say that the only useful serialtype is BYTEA --- which, in practice, is the only interesting value anyway, due to the usefulness of the send/recv infrastructure for this purpose. That means we only have to allow "serialize(internal) returns bytea" and "deserialize(bytea, internal) returns internal" as the signatures for these support functions. In passing fix bogus signature of int4_avg_combine, which I found thanks to adding an opr_sanity check on combinefunc signatures. catversion bump due to removing pg_aggregate.aggserialtype and adjusting signatures of assorted built-in functions. David Rowley and Tom Lane Discussion: <27247.1466185504@sss.pgh.pa.us>	10 years ago
Robert Haas	4bc424b968	pgindent run for 9.6	10 years ago
Alvaro Herrera	f2fcad27d5	Support ALTER THING .. DEPENDS ON EXTENSION ... This introduces a new dependency type which marks an object as depending on an extension, such that if the extension is dropped, the object automatically goes away; and also, if the database is dumped, the object is included in the dump output. Currently the grammar supports this for indexes, triggers, materialized views and functions only, although the utility code is generic so adding support for more object types is a matter of touching the parser rules only. Author: Abhijit Menon-Sen Reviewed-by: Alexander Korotkov, Álvaro Herrera Discussion: http://www.postgresql.org/message-id/20160115062649.GA5068@toroid.org	10 years ago
Robert Haas	5fe5a2cee9	Allow aggregate transition states to be serialized and deserialized. ... This is necessary infrastructure for supporting parallel aggregation for aggregates whose transition type is "internal". Such values can't be passed between cooperating processes, because they are just pointers. David Rowley, reviewed by Tomas Vondra and by me.	10 years ago
Alvaro Herrera	473b932870	Support CREATE ACCESS METHOD ... This enables external code to create access methods. This is useful so that extensions can add their own access methods which can be formally tracked for dependencies, so that DROP operates correctly. Also, having explicit support makes pg_dump work correctly. Currently only index AMs are supported, but we expect different types to be added in the future. Authors: Alexander Korotkov, Petr Jelínek Reviewed-By: Teodor Sigaev, Petr Jelínek, Jim Nasby Commitfest-URL: https://commitfest.postgresql.org/9/353/ Discussion: https://www.postgresql.org/message-id/CAPpHfdsXwZmojm6Dx+TJnpYk27kT4o7Ri6X_4OSWcByu1Rm+VA@mail.gmail.com	10 years ago
Tom Lane	2c6af4f442	Move keywords.c/kwlookup.c into src/common/. ... Now that we have src/common/ for code shared between frontend and backend, we can get rid of (most of) the klugy ways that the keyword table and keyword lookup code were formerly shared between different uses. This is a first step towards a more general plan of getting rid of special-purpose kluges for sharing code in src/bin/. I chose to merge kwlookup.c back into keywords.c, as it once was, and always has been so far as keywords.h is concerned. We could have kept them separate, but there is noplace that uses ScanKeywordLookup without also wanting access to the backend's keyword list, so there seems little point. ecpg is still a bit weird, but at least now the trickiness is documented. I think that the MSVC build script should require no adjustments beyond what's done here ... but we'll soon find out.	10 years ago
Teodor Sigaev	3187d6de0e	Introduce parse_ident() ... SQL-layer function to split qualified identifier into array parts. Author: Pavel Stehule with minor editorization by me and Jim Nasby	10 years ago
Robert Haas	a7de3dc5c3	Support multi-stage aggregation. ... Aggregate nodes now have two new modes: a "partial" mode where they output the unfinalized transition state, and a "finalize" mode where they accept unfinalized transition states rather than individual values as input. These new modes are not used anywhere yet, but they will be necessary for parallel aggregation. The infrastructure also figures to be useful for cases where we want to aggregate local data and remote data via the FDW interface, and want to bring back partial aggregates from the remote side that can then be combined with locally generated partial aggregates to produce the final value. It may also be useful even when neither FDWs nor parallelism are in play, as explained in the comments in nodeAgg.c. David Rowley and Simon Riggs, reviewed by KaiGai Kohei, Heikki Linnakangas, Haribabu Kommi, and me.	10 years ago
Bruce Momjian	ee94300446	Update copyright for 2016 ... Backpatch certain files through 9.1	10 years ago
Robert Haas	7aea8e4f2d	Determine whether it's safe to attempt a parallel plan for a query. ... Commit 924bcf4f16 introduced a framework for parallel computation in PostgreSQL that makes most but not all built-in functions safe to execute in parallel mode. In order to have parallel query, we'll need to be able to determine whether that query contains functions (either built-in or user-defined) that cannot be safely executed in parallel mode. This requires those functions to be labeled, so this patch introduces an infrastructure for that. Some functions currently labeled as safe may need to be revised depending on how pending issues related to heavyweight locking under paralllelism are resolved. Parallel plans can't be used except for the case where the query will run to completion. If portal execution were suspended, the parallel mode restrictions would need to remain in effect during that time, but that might make other queries fail. Therefore, this patch introduces a framework that enables consideration of parallel plans only when it is known that the plan will be run to completion. This probably needs some refinement; for example, at bind time, we do not know whether a query run via the extended protocol will be execution to completion or run with a limited fetch count. Having the client indicate its intentions at bind time would constitute a wire protocol break. Some contexts in which parallel mode would be safe are not adjusted by this patch; the default is not to try parallel plans except from call sites that have been updated to say that such plans are OK. This commit doesn't introduce any parallel paths or plans; it just provides a way to determine whether they could potentially be used. I'm committing it on the theory that the remaining parallel sequential scan patches will also get committed to this release, hopefully in the not-too-distant future. Robert Haas and Amit Kapila. Reviewed (in earlier versions) by Noah Misch.	10 years ago
Heikki Linnakangas	804163bc25	Share transition state between different aggregates when possible. ... If there are two different aggregates in the query with same inputs, and the aggregates have the same initial condition and transition function, only calculate the state value once, and only call the final functions separately. For example, AVG(x) and SUM(x) aggregates have the same transition function, which accumulates the sum and number of input tuples. For a query like "SELECT AVG(x), SUM(x) FROM x", we can therefore accumulate the state function only once, which gives a nice speedup. David Rowley, reviewed and edited by me.	11 years ago
Joe Conway	632cd9f892	Create new ParseExprKind for use by policy expressions. ... Policy USING and WITH CHECK expressions were using EXPR_KIND_WHERE for parse analysis, which results in inappropriate ERROR messages when the expression contains unsupported constructs such as aggregates. Create a new ParseExprKind called EXPR_KIND_POLICY and tailor the related messages to fit. Reported by Noah Misch. Reviewed by Dean Rasheed, Alvaro Herrera, and Robert Haas. Back-patch to 9.5 where RLS was introduced.	11 years ago
Tom Lane	dd7a8f66ed	Redesign tablesample method API, and do extensive code review. ... The original implementation of TABLESAMPLE modeled the tablesample method API on index access methods, which wasn't a good choice because, without specialized DDL commands, there's no way to build an extension that can implement a TSM. (Raw inserts into system catalogs are not an acceptable thing to do, because we can't undo them during DROP EXTENSION, nor will pg_upgrade behave sanely.) Instead adopt an API more like procedural language handlers or foreign data wrappers, wherein the only SQL-level support object needed is a single handler function identified by having a special return type. This lets us get rid of the supporting catalog altogether, so that no custom DDL support is needed for the feature. Adjust the API so that it can support non-constant tablesample arguments (the original coding assumed we could evaluate the argument expressions at ExecInitSampleScan time, which is undesirable even if it weren't outright unsafe), and discourage sampling methods from looking at invisible tuples. Make sure that the BERNOULLI and SYSTEM methods are genuinely repeatable within and across queries, as required by the SQL standard, and deal more honestly with methods that can't support that requirement. Make a full code-review pass over the tablesample additions, and fix assorted bugs, omissions, infelicities, and cosmetic issues (such as failure to put the added code stanzas in a consistent ordering). Improve EXPLAIN's output of tablesample plans, too. Back-patch to 9.5 so that we don't have to support the original API in production.	11 years ago
Andres Freund	c1ca3a19df	Fix bug around assignment expressions containing indirections. ... Handling of assigned-to expressions with indirection (e.g. set f1[1] = 3) was broken for ON CONFLICT DO UPDATE. The problem was that ParseState was consulted to determine if an INSERT-appropriate or UPDATE-appropriate behavior should be used when transforming expressions with indirections. When the wrong path was taken the old row was substituted with NULL, leading to wrong results.. To fix remove p_is_update and only use p_is_insert to decide how to transform the assignment expression, and uset p_is_insert while parsing the on conflict statement. This isn't particularly pretty, but it's not any worse than before. Author: Peter Geoghegan, slightly edited by me Discussion: CAM3SWZS8RPvA=KFxADZWw3wAHnnbxMxDzkEC6fNaFc7zSm411w@mail.gmail.com Backpatch: 9.5, where the feature was introduced	11 years ago
Bruce Momjian	807b9e0dff	pgindent run for 9.5	11 years ago
Andres Freund	f3d3118532	Support GROUPING SETS, CUBE and ROLLUP. ... This SQL standard functionality allows to aggregate data by different GROUP BY clauses at once. Each grouping set returns rows with columns grouped by in other sets set to NULL. This could previously be achieved by doing each grouping as a separate query, conjoined by UNION ALLs. Besides being considerably more concise, grouping sets will in many cases be faster, requiring only one scan over the underlying data. The current implementation of grouping sets only supports using sorting for input. Individual sets that share a sort order are computed in one pass. If there are sets that don't share a sort order, additional sort & aggregation steps are performed. These additional passes are sourced by the previous sort step; thus avoiding repeated scans of the source data. The code is structured in a way that adding support for purely using hash aggregation or a mix of hashing and sorting is possible. Sorting was chosen to be supported first, as it is the most generic method of implementation. Instead of, as in an earlier versions of the patch, representing the chain of sort and aggregation steps as full blown planner and executor nodes, all but the first sort are performed inside the aggregation node itself. This avoids the need to do some unusual gymnastics to handle having to return aggregated and non-aggregated tuples from underlying nodes, as well as having to shut down underlying nodes early to limit memory usage. The optimizer still builds Sort/Agg node to describe each phase, but they're not part of the plan tree, but instead additional data for the aggregation node. They're a convenient and preexisting way to describe aggregation and sorting. The first (and possibly only) sort step is still performed as a separate execution step. That retains similarity with existing group by plans, makes rescans fairly simple, avoids very deep plans (leading to slow explains) and easily allows to avoid the sorting step if the underlying data is sorted by other means. A somewhat ugly side of this patch is having to deal with a grammar ambiguity between the new CUBE keyword and the cube extension/functions named cube (and rollup). To avoid breaking existing deployments of the cube extension it has not been renamed, neither has cube been made a reserved keyword. Instead precedence hacking is used to make GROUP BY cube(..) refer to the CUBE grouping sets feature, and not the function cube(). To actually group by a function cube(), unlikely as that might be, the function name has to be quoted. Needs a catversion bump because stored rules may change. Author: Andrew Gierth and Atri Sharma, with contributions from Andres Freund Reviewed-By: Andres Freund, Noah Misch, Tom Lane, Svenne Krap, Tomas Vondra, Erik Rijkers, Marti Raudsepp, Pavel Stehule Discussion: CAOeZVidmVRe2jU6aMk_5qkxnB7dfmPROzM7Ur8JPW5j8Y5X-Lw@mail.gmail.com	11 years ago
Simon Riggs	f6d208d6e5	TABLESAMPLE, SQL Standard and extensible ... Add a TABLESAMPLE clause to SELECT statements that allows user to specify random BERNOULLI sampling or block level SYSTEM sampling. Implementation allows for extensible sampling functions to be written, using a standard API. Basic version follows SQLStandard exactly. Usable concrete use cases for the sampling API follow in later commits. Petr Jelinek Reviewed by Michael Paquier and Simon Riggs	11 years ago
Andres Freund	168d5805e4	Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. ... The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.	11 years ago
Peter Eisentraut	cac7658205	Add transforms feature ... This provides a mechanism for specifying conversions between SQL data types and procedural languages. As examples, there are transforms for hstore and ltree for PL/Perl and PL/Python. reviews by Pavel Stěhule and Andres Freund	11 years ago
Tom Lane	785941cdc3	Tweak __attribute__-wrapping macros for better pgindent results. ... This improves on commit bbfd7edae5 by making two simple changes: * pg_attribute_noreturn now takes parentheses, ie pg_attribute_noreturn(). Likewise pg_attribute_unused(), pg_attribute_packed(). This reduces pgindent's tendency to misformat declarations involving them. * attributes are now always attached to function declarations, not definitions. Previously some places were taking creative shortcuts, which were not merely candidates for bad misformatting by pgindent but often were outright wrong anyway. (It does little good to put a noreturn annotation where callers can't see it.) In any case, if we would like to believe that these macros can be used with non-gcc compilers, we should avoid gratuitous variance in usage patterns. I also went through and manually improved the formatting of a lot of declarations, and got rid of excessively repetitive (and now obsolete anyway) comments informing the reader what pg_attribute_printf is for.	11 years ago
Tom Lane	7b8b8a4331	Improve representation of PlanRowMark. ... This patch fixes two inadequacies of the PlanRowMark representation. First, that the original LockingClauseStrength isn't stored (and cannot be inferred for foreign tables, which always get ROW_MARK_COPY). Since some PlanRowMarks are created out of whole cloth and don't actually have an ancestral RowMarkClause, this requires adding a dummy LCS_NONE value to enum LockingClauseStrength, which is fairly annoying but the alternatives seem worse. This fix allows getting rid of the use of get_parse_rowmark() in FDWs (as per the discussion around commits 462bd95705 and 8ec8760fc8), and it simplifies some things elsewhere. Second, that the representation assumed that all child tables in an inheritance hierarchy would use the same RowMarkType. That's true today but will soon not be true. We add an "allMarkTypes" field that identifies the union of mark types used in all a parent table's children, and use that where appropriate (currently, only in preprocess_targetlist()). In passing fix a couple of minor infelicities left over from the SKIP LOCKED patch, notably that _outPlanRowMark still thought waitPolicy is a bool. Catversion bump is required because the numeric values of enum LockingClauseStrength can appear in on-disk rules. Extracted from a much larger patch to support foreign table inheritance; it seemed worth breaking this out, since it's a separable concern. Shigeru Hanada and Etsuro Fujita, somewhat modified by me	11 years ago
Tom Lane	c6b3c939b7	Make operator precedence follow the SQL standard more closely. ... While the SQL standard is pretty vague on the overall topic of operator precedence (because it never presents a unified BNF for all expressions), it does seem reasonable to conclude from the spec for <boolean value expression> that OR has the lowest precedence, then AND, then NOT, then IS tests, then the six standard comparison operators, then everything else (since any non-boolean operator in a WHERE clause would need to be an argument of one of these). We were only sort of on board with that: most notably, while "<" ">" and "=" had properly low precedence, "<=" ">=" and "<>" were treated as generic operators and so had significantly higher precedence. And "IS" tests were even higher precedence than those, which is very clearly wrong per spec. Another problem was that "foo NOT SOMETHING bar" constructs, such as "x NOT LIKE y", were treated inconsistently because of a bison implementation artifact: they had the documented precedence with respect to operators to their right, but behaved like NOT (i.e., very low priority) with respect to operators to their left. Fixing the precedence issues is just a small matter of rearranging the precedence declarations in gram.y, except for the NOT problem, which requires adding an additional lookahead case in base_yylex() so that we can attach a different token precedence to NOT LIKE and allied two-word operators. The bulk of this patch is not the bug fix per se, but adding logic to parse_expr.c to allow giving warnings if an expression has changed meaning because of these precedence changes. These warnings are off by default and are enabled by the new GUC operator_precedence_warning. It's believed that very few applications will be affected by these changes, but it was agreed that a warning mechanism is essential to help debug any that are.	11 years ago
Robert Haas	e529cd4ffa	Suggest to the user the column they may have meant to reference. ... Error messages informing the user that no such column exists can sometimes provoke a perplexed response. This often happens due to a subtle typo in the column name or, perhaps less likely, in the alias name. To speed discovery of what the real issue is in such cases, we'll now search the range table for approximate matches. If there are one or two such matches that are good enough to think that they might be what the user intended to type, and better than all other approximate matches, we'll issue a hint suggesting that the user might have intended to reference those columns. Peter Geoghegan and Robert Haas	11 years ago
Andres Freund	bbfd7edae5	Add macros wrapping all usage of gcc's __attribute__. ... Until now __attribute__() was defined to be empty for all compilers but gcc. That's problematic because it prevents using it in other compilers; which is necessary e.g. for atomics portability. It's also just generally dubious to do so in a header as widely included as c.h. Instead add pg_attribute_format_arg, pg_attribute_printf, pg_attribute_noreturn macros which are implemented in the compilers that understand them. Also add pg_attribute_noreturn and pg_attribute_packed, but don't provide fallbacks, since they can affect functionality. This means that external code that, possibly unwittingly, relied on __attribute__ defined to be empty on !gcc compilers may now run into warnings or errors on those compilers. But there shouldn't be many occurances of that and it's hard to work around... Discussion: 54B58BA3.8040302@ohmu.fi Author: Oskari Saarenmaa, with some minor changes by me.	11 years ago
Tom Lane	2fbb286647	Clean up the mess from => patch. ... Commit 865f14a2d3 was quite a few bricks shy of a load: psql, ecpg, and plpgsql were all left out-of-step with the core lexer. Of these only the last was likely to be a fatal problem; but still, a minimal amount of grepping, or even just reading the comments adjacent to the places that were changed, would have found the other places that needed to be changed.	11 years ago
Tom Lane	d809fd0008	Improve parser's one-extra-token lookahead mechanism. ... There are a couple of places in our grammar that fail to be strict LALR(1), by requiring more than a single token of lookahead to decide what to do. Up to now we've dealt with that by using a filter between the lexer and parser that merges adjacent tokens into one in the places where two tokens of lookahead are necessary. But that creates a number of user-visible anomalies, for instance that you can't name a CTE "ordinality" because "WITH ordinality AS ..." triggers folding of WITH and ORDINALITY into one token. I realized that there's a better way. In this patch, we still do the lookahead basically as before, but we never merge the second token into the first; we replace just the first token by a special lookahead symbol when one of the lookahead pairs is seen. This requires a couple extra productions in the grammar, but it involves fewer special tokens, so that the grammar tables come out a bit smaller than before. The filter logic is no slower than before, perhaps a bit faster. I also fixed the filter logic so that when backing up after a lookahead, the current token's terminator is correctly restored; this eliminates some weird behavior in error message issuance, as is shown by the one change in existing regression test outputs. I believe that this patch entirely eliminates odd behaviors caused by lookahead for WITH. It doesn't really improve the situation for NULLS followed by FIRST/LAST unfortunately: those sequences still act like a reserved word, even though there are cases where they should be seen as two ordinary identifiers, eg "SELECT nulls first FROM ...". I experimented with additional grammar hacks but couldn't find any simple solution for that. Still, this is better than before, and it seems much more likely that we *could* somehow solve the NULLS case on the basis of this filter behavior than the previous one.	11 years ago
Tom Lane	eb213acfe2	Prevent duplicate escape-string warnings when using pg_stat_statements. ... contrib/pg_stat_statements will sometimes run the core lexer a second time on submitted statements. Formerly, if you had standard_conforming_strings turned off, this led to sometimes getting two copies of any warnings enabled by escape_string_warning. While this is probably no longer a big deal in the field, it's a pain for regression testing. To fix, change the lexer so it doesn't consult the escape_string_warning GUC variable directly, but looks at a copy in the core_yy_extra_type state struct. Then, pg_stat_statements can change that copy to disable warnings while it's redoing the lexing. It seemed like a good idea to make this happen for all three of the GUCs consulted by the lexer, not just escape_string_warning. There's not an immediate use-case for callers to adjust the other two AFAIK, but making it possible is easy enough and seems like good future-proofing. Arguably this is a bug fix, but there doesn't seem to be enough interest to justify a back-patch. We'd not be able to back-patch exactly as-is anyway, for fear of breaking ABI compatibility of the struct. (We could perhaps back-patch the addition of only escape_string_warning by adding it at the end of the struct, where there's currently alignment padding space.)	11 years ago
Bruce Momjian	4baaf863ec	Update copyright for 2015 ... Backpatch certain files through 9.0	11 years ago
Alvaro Herrera	d7ee82e50f	Add SQL-callable pg_get_object_address ... This allows access to get_object_address from SQL, which is useful to obtain OID addressing information from data equivalent to that emitted by the parser. This is necessary infrastructure of a project to let replication systems propagate object dropping events to remote servers, where the schema might be different than the server originating the DROP. This patch also adds support for OBJECT_DEFAULT to get_object_address; that is, it is now possible to refer to a column's default value. Catalog version bumped due to the new function. Reviewed by Stephen Frost, Heikki Linnakangas, Robert Haas, Andres Freund, Abhijit Menon-Sen, Adam Brightwell.	11 years ago
Alvaro Herrera	e4d1e26491	Remove unused InhPaths ... Allegedly, the last remaining usages of that struct were removed by 0e99be1c. Author: Peter Geoghegan	11 years ago
Alvaro Herrera	df630b0dd5	Implement SKIP LOCKED for row-level locks ... This clause changes the behavior of SELECT locking clauses in the presence of locked rows: instead of causing a process to block waiting for the locks held by other processes (or raise an error, with NOWAIT), SKIP LOCKED makes the new reader skip over such rows. While this is not appropriate behavior for general purposes, there are some cases in which it is useful, such as queue-like tables. Catalog version bumped because this patch changes the representation of stored rules. Reviewed by Craig Ringer (based on a previous attempt at an implementation by Simon Riggs, who also provided input on the syntax used in the current patch), David Rowley, and Álvaro Herrera. Author: Thomas Munro	11 years ago
Stephen Frost	491c029dbc	Row-Level Security Policies (RLS) ... Building on the updatable security-barrier views work, add the ability to define policies on tables to limit the set of rows which are returned from a query and which are allowed to be added to a table. Expressions defined by the policy for filtering are added to the security barrier quals of the query, while expressions defined to check records being added to a table are added to the with-check options of the query. New top-level commands are CREATE/ALTER/DROP POLICY and are controlled by the table owner. Row Security is able to be enabled and disabled by the owner on a per-table basis using ALTER TABLE .. ENABLE/DISABLE ROW SECURITY. Per discussion, ROW SECURITY is disabled on tables by default and must be enabled for policies on the table to be used. If no policies exist on a table with ROW SECURITY enabled, a default-deny policy is used and no records will be visible. By default, row security is applied at all times except for the table owner and the superuser. A new GUC, row_security, is added which can be set to ON, OFF, or FORCE. When set to FORCE, row security will be applied even for the table owner and superusers. When set to OFF, row security will be disabled when allowed and an error will be thrown if the user does not have rights to bypass row security. Per discussion, pg_dump sets row_security = OFF by default to ensure that exports and backups will have all data in the table or will error if there are insufficient privileges to bypass row security. A new option has been added to pg_dump, --enable-row-security, to ask pg_dump to export with row security enabled. A new role capability, BYPASSRLS, which can only be set by the superuser, is added to allow other users to be able to bypass row security using row_security = OFF. Many thanks to the various individuals who have helped with the design, particularly Robert Haas for his feedback. Authors include Craig Ringer, KaiGai Kohei, Adam Brightwell, Dean Rasheed, with additional changes and rework by me. Reviewers have included all of the above, Greg Smith, Jeff McCormick, and Robert Haas.	11 years ago
Alvaro Herrera	f41872d0c1	Implement ALTER TABLE .. SET LOGGED / UNLOGGED ... This enables changing permanent (logged) tables to unlogged and vice-versa. (Docs for ALTER TABLE / SET TABLESPACE got shuffled in an order that hopefully makes more sense than the original.) Author: Fabrízio de Royes Mello Reviewed by: Christoph Berg, Andres Freund, Thom Brown Some tweaking by Álvaro Herrera	12 years ago