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* Add temporal FOREIGN KEY contraintsPeter Eisentraut2024-09-17
| | | | | | | | | | | | | | | | | | | | | Add PERIOD clause to foreign key constraint definitions. This is supported for range and multirange types. Temporal foreign keys check for range containment instead of equality. This feature matches the behavior of the SQL standard temporal foreign keys, but it works on PostgreSQL's native ranges instead of SQL's "periods", which don't exist in PostgreSQL (yet). Reference actions ON {UPDATE,DELETE} {CASCADE,SET NULL,SET DEFAULT} are not supported yet. (previously committed as 34768ee3616, reverted by 8aee330af55; this is essentially unchanged from those) Author: Paul A. Jungwirth <pj@illuminatedcomputing.com> Reviewed-by: Peter Eisentraut <peter@eisentraut.org> Reviewed-by: jian he <jian.universality@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
* Add temporal PRIMARY KEY and UNIQUE constraintsPeter Eisentraut2024-09-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Add WITHOUT OVERLAPS clause to PRIMARY KEY and UNIQUE constraints. These are backed by GiST indexes instead of B-tree indexes, since they are essentially exclusion constraints with = for the scalar parts of the key and && for the temporal part. (previously committed as 46a0cd4cefb, reverted by 46a0cd4cefb; the new part is this:) Because 'empty' && 'empty' is false, the temporal PK/UQ constraint allowed duplicates, which is confusing to users and breaks internal expectations. For instance, when GROUP BY checks functional dependencies on the PK, it allows selecting other columns from the table, but in the presence of duplicate keys you could get the value from any of their rows. So we need to forbid empties. This all means that at the moment we can only support ranges and multiranges for temporal PK/UQs, unlike the original patch (above). Documentation and tests for this are added. But this could conceivably be extended by introducing some more general support for the notion of "empty" for other types. Author: Paul A. Jungwirth <pj@illuminatedcomputing.com> Reviewed-by: Peter Eisentraut <peter@eisentraut.org> Reviewed-by: jian he <jian.universality@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
* Use a hash table to de-duplicate column names in ruleutils.c.Tom Lane2024-09-10
| | | | | | | | | | | | | | | | | | | Commit 8004953b5 added a hash table to avoid O(N^2) cost in choosing unique relation aliases while deparsing a view or rule. It did nothing about the similar O(N^2) (maybe worse) costs of choosing unique column aliases within each RTE. However, that's now demonstrably a bottleneck when deparsing CHECK constraints for wide tables, so let's use a similar hash table to handle those. The extra cost of setting up the hash table will not be repaid unless the table has many columns. I've set this up so that we use the brute force method if there are less than 32 columns. The exact cutoff is not too critical, but this value seems good because it results in both code paths getting exercised by existing regression-test cases. Patch by me; thanks to David Rowley for review. Discussion: https://postgr.es/m/2885468.1722291250@sss.pgh.pa.us
* Introduce an RTE for the grouping stepRichard Guo2024-09-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If there are subqueries in the grouping expressions, each of these subqueries in the targetlist and HAVING clause is expanded into distinct SubPlan nodes. As a result, only one of these SubPlan nodes would be converted to reference to the grouping key column output by the Agg node; others would have to get evaluated afresh. This is not efficient, and with grouping sets this can cause wrong results issues in cases where they should go to NULL because they are from the wrong grouping set. Furthermore, during re-evaluation, these SubPlan nodes might use nulled column values from grouping sets, which is not correct. This issue is not limited to subqueries. For other types of expressions that are part of grouping items, if they are transformed into another form during preprocessing, they may fail to match lower target items. This can also lead to wrong results with grouping sets. To fix this issue, we introduce a new kind of RTE representing the output of the grouping step, with columns that are the Vars or expressions being grouped on. In the parser, we replace the grouping expressions in the targetlist and HAVING clause with Vars referencing this new RTE, so that the output of the parser directly expresses the semantic requirement that the grouping expressions be gotten from the grouping output rather than computed some other way. In the planner, we first preprocess all the columns of this new RTE and then replace any Vars in the targetlist and HAVING clause that reference this new RTE with the underlying grouping expressions, so that we will have only one instance of a SubPlan node for each subquery contained in the grouping expressions. Bump catversion because this changes the querytree produced by the parser. Thanks to Tom Lane for the idea to invent a new kind of RTE. Per reports from Geoff Winkless, Tobias Wendorff, Richard Guo from various threads. Author: Richard Guo Reviewed-by: Ashutosh Bapat, Sutou Kouhei Discussion: https://postgr.es/m/CAMbWs4_dp7e7oTwaiZeBX8+P1rXw4ThkZxh1QG81rhu9Z47VsQ@mail.gmail.com
* Don't bother checking the result of SPI_connect[_ext] anymore.Tom Lane2024-09-09
| | | | | | | | | | | | | | | | | | | | | | | SPI_connect/SPI_connect_ext have not returned any value other than SPI_OK_CONNECT since commit 1833f1a1c in v10; any errors are thrown via ereport. (The most likely failure is out-of-memory, which has always been thrown that way, so callers had better be prepared for such errors.) This makes it somewhat pointless to check these functions' result, and some callers within our code haven't been bothering; indeed, the only usage example within spi.sgml doesn't bother. So it's likely that the omission has propagated into extensions too. Hence, let's standardize on not checking, and document the return value as historical, while not actually changing these functions' behavior. (The original proposal was to change their return type to "void", but that would needlessly break extensions that are conforming to the old practice.) This saves a small amount of boilerplate code in a lot of places. Stepan Neretin Discussion: https://postgr.es/m/CAMaYL5Z9Uk8cD9qGz9QaZ2UBJFOu7jFx5Mwbznz-1tBbPDQZow@mail.gmail.com
* SQL/JSON: Fix default ON ERROR behavior for JSON_TABLEAmit Langote2024-09-06
| | | | | | | | | | | | Use EMPTY ARRAY instead of EMPTY. This change does not affect the runtime behavior of JSON_TABLE(), which continues to return an empty relation ON ERROR. It only alters whether the default ON ERROR behavior is shown in the deparsed output. Reported-by: Jian He <jian.universality@gmail.com> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
* SQL/JSON: Fix JSON_TABLE() column deparsingAmit Langote2024-09-06
| | | | | | | | | | | | | | | | The deparsing code in get_json_expr_options() unnecessarily emitted the default column-specific ON ERROR / EMPTY behavior when the top-level ON ERROR behavior in JSON_TABLE was set to ERROR. Fix that by not overriding the column-specific default, determined based on the column's JsonExprOp in get_json_table_columns(), with JSON_BEHAVIOR_ERROR when that is the top-level ON ERROR behavior. Note that this only removes redundancy; the current deparsing output is not incorrect, just redundant. Reviewed-by: Jian He <jian.universality@gmail.com> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
* Revert recent SQL/JSON related commitsAmit Langote2024-09-06
| | | | | Reverts 68222851d5a8, 565caaa79af, and 3a97460970f, because a few BF animals didn't like one or all of them.
* SQL/JSON: Fix default ON ERROR behavior for JSON_TABLEAmit Langote2024-09-06
| | | | | | | | | | | | Use EMPTY ARRAY instead of EMPTY. This change does not affect the runtime behavior of JSON_TABLE(), which continues to return an empty relation ON ERROR. It only alters whether the default ON ERROR behavior is shown in the deparsed output. Reported-by: Jian He <jian.universality@gmail.com> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
* SQL/JSON: Fix JSON_TABLE() column deparsingAmit Langote2024-09-06
| | | | | | | | | | | | | | | | The deparsing code in get_json_expr_options() unnecessarily emitted the default column-specific ON ERROR / EMPTY behavior when the top-level ON ERROR behavior in JSON_TABLE was set to ERROR. Fix that by not overriding the column-specific default, determined based on the column's JsonExprOp in get_json_table_columns(), with JSON_BEHAVIOR_ERROR when that is the top-level ON ERROR behavior. Note that this only removes redundancy; the current deparsing output is not incorrect, just redundant. Reviewed-by: Jian He <jian.universality@gmail.com> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
* Fix mis-deparsing of ORDER BY lists when there is a name conflict.Tom Lane2024-08-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If an ORDER BY item in SELECT is a bare identifier, the parser first seeks it as an output column name of the SELECT (for SQL92 compatibility). However, ruleutils.c is expecting the SQL99 interpretation where such a name is an input column name. So it's possible to produce an incorrect display of a view in the (admittedly pretty ill-advised) case where some other column is renamed in the SELECT output list to match an ORDER BY column. This can be fixed by table-qualifying such names in the dumped view text. To avoid cluttering less-ill-advised queries, we'd like to do so only when there's an actual name conflict. That requires passing the current get_query_def call's resultDesc parameter down to get_variable, so that it can determine what the output column names are. In hopes of reducing rather than increasing notational clutter in ruleutils.c, I moved that value into the deparse_context struct and removed it from the parameter lists of get_query_def's other subroutines. I made a few other cosmetic changes while at it: * Likewise move the colNamesVisible parameter into deparse_context. * Rename deparse_context's windowTList field to targetList, since it's no longer used only in connection with WINDOW clauses. * Replace the special_exprkind field with a bool inGroupBy, since that was all it was being used for, and the apparent flexibility of storing a ParseExprKind proved to be illusory. (We need a separate varInOrderBy field to make this patch work.) * Remove useless save/restore logic in get_select_query_def. In principle, this bug is quite old. However, it seems unreachable before 1b4d280ea, because before that the presence of "new" and "old" entries in a view's rangetable caused us to always table-qualify every Var reference in dumped views. Hence, back-patch to v16 where that came in. Per bug #18589 from Quynh Tran. Discussion: https://postgr.es/m/18589-70091cb81db1a3f1@postgresql.org
* Revert support for ALTER TABLE ... MERGE/SPLIT PARTITION(S) commandsAlexander Korotkov2024-08-24
| | | | | | | | | | | | | | | | | This commit reverts 1adf16b8fb, 87c21bb941, and subsequent fixes and improvements including df64c81ca9, c99ef1811a, 9dfcac8e15, 885742b9f8, 842c9b2705, fcf80c5d5f, 96c7381c4c, f4fc7cb54b, 60ae37a8bc, 259c96fa8f, 449cdcd486, 3ca43dbbb6, 2a679ae94e, 3a82c689fd, fbd4321fd5, d53a4286d7, c086896625, 4e5d6c4091, 04158e7fa3. The reason for reverting is security issues related to repeatable name lookups (CVE-2014-0062). Even though 04158e7fa3 solved part of the problem, there are still remaining issues, which aren't feasible to even carefully analyze before the RC deadline. Reported-by: Noah Misch, Robert Haas Discussion: https://postgr.es/m/20240808171351.a9.nmisch%40google.com Backpatch-through: 17
* Suppress Coverity warnings about Asserts in get_name_for_var_field.Tom Lane2024-08-11
| | | | | | | | | Coverity thinks dpns->plan could be null at these points. That shouldn't really be possible, but it's easy enough to modify the Asserts so they'd not core-dump if it were true. These are new in b919a97a6. Back-patch to v13; the v12 version of the patch didn't have these Asserts.
* Fix "failed to find plan for subquery/CTE" errors in EXPLAIN.Tom Lane2024-08-09
| | | | | | | | | | | | | | | | | | | | | | To deparse a reference to a field of a RECORD-type output of a subquery, EXPLAIN normally digs down into the subquery's plan to try to discover exactly which anonymous RECORD type is meant. However, this can fail if the subquery has been optimized out of the plan altogether on the grounds that no rows could pass the WHERE quals, which has been possible at least since 3fc6e2d7f. There isn't anything remaining in the plan tree that would help us, so fall back to printing the field name as "fN" for the N'th column of the record. (This will actually be the right thing some of the time, since it matches the column names we assign to RowExprs.) In passing, fix a comment typo in create_projection_plan, which I noticed while experimenting with an alternative fix for this. Per bug #18576 from Vasya B. Back-patch to all supported branches. Richard Guo and Tom Lane Discussion: https://postgr.es/m/18576-9feac34e132fea9e@postgresql.org
* Fix another couple of outdated comments for MERGE RETURNING.Dean Rasheed2024-06-04
| | | | | | Oversights in c649fa24a4 which added RETURNING support to MERGE. Discussion: https://postgr.es/m/CAApHDvpqp6vtUzG-_josUEiBGyqnrnVxJ-VdF+hJLXjHdHzsyQ@mail.gmail.com
* Revert temporal primary keys and foreign keysPeter Eisentraut2024-05-16
| | | | | | | | | | | | | | | | | | | | This feature set did not handle empty ranges correctly, and it's now too late for PostgreSQL 17 to fix it. The following commits are reverted: 6db4598fcb8 Add stratnum GiST support function 46a0cd4cefb Add temporal PRIMARY KEY and UNIQUE constraints 86232a49a43 Fix comment on gist_stratnum_btree 030e10ff1a3 Rename pg_constraint.conwithoutoverlaps to conperiod a88c800deb6 Use daterange and YMD in without_overlaps tests instead of tsrange. 5577a71fb0c Use half-open interval notation in without_overlaps tests 34768ee3616 Add temporal FOREIGN KEY contraints 482e108cd38 Add test for REPLICA IDENTITY with a temporal key c3db1f30cba doc: clarify PERIOD and WITHOUT OVERLAPS in CREATE TABLE 144c2ce0cc7 Fix ON CONFLICT DO NOTHING/UPDATE for temporal indexes Discussion: https://www.postgresql.org/message-id/d0b64a7a-dfe4-4b84-a906-c7dedfa40a3e@eisentraut.org
* Revert structural changes to not-null constraintsAlvaro Herrera2024-05-13
| | | | | | | | | | | | | | | | | | | | | | | | | There are some problems with the new way to handle these constraints that were detected at the last minute, and require fixes that appear too invasive to be doing this late in the cycle. Revert this (again) for now, we'll try again with these problems fixed. The following commits are reverted: b0e96f311985 Catalog not-null constraints 9b581c534186 Disallow changing NO INHERIT status of a not-null constraint d0ec2ddbe088 Fix not-null constraint test ac22a9545ca9 Move privilege check to the right place b0f7dd915bca Check stack depth in new recursive functions 3af721794272 Update information_schema definition for not-null constraints c3709100be73 Fix propagating attnotnull in multiple inheritance d9f686a72ee9 Fix restore of not-null constraints with inheritance d72d32f52d26 Don't try to assign smart names to constraints 0cd711271d42 Better handle indirect constraint drops 13daa33fa5a6 Disallow NO INHERIT not-null constraints on partitioned tables d45597f72fe5 Disallow direct change of NO INHERIT of not-null constraints 21ac38f498b3 Fix inconsistencies in error messages Discussion: https://postgr.es/m/202405110940.joxlqcx4dogd@alvherre.pgsql
* Fix an assortment of typosDavid Rowley2024-05-04
| | | | | Author: Alexander Lakhin Discussion: https://postgr.es/m/ae9f2fcb-4b24-5bb0-4240-efbbbd944ca1@gmail.com
* Fix ALTER DOMAIN NOT NULL syntaxPeter Eisentraut2024-04-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This addresses a few problems with commit e5da0fe3c22 ("Catalog domain not-null constraints"). In CREATE DOMAIN, a NOT NULL constraint looks like CREATE DOMAIN d1 AS int [ CONSTRAINT conname ] NOT NULL (Before e5da0fe3c22, the constraint name was accepted but ignored.) But in ALTER DOMAIN, a NOT NULL constraint looks like ALTER DOMAIN d1 ADD [ CONSTRAINT conname ] NOT NULL VALUE where VALUE is where for a table constraint the column name would be. (This works as of e5da0fe3c22. Before e5da0fe3c22, this syntax resulted in an internal error.) But for domains, this latter syntax is confusing and needlessly inconsistent between CREATE and ALTER. So this changes it to just ALTER DOMAIN d1 ADD [ CONSTRAINT conname ] NOT NULL (None of these syntaxes are per SQL standard; we are just living with the bits of inconsistency that have built up over time.) In passing, this also changes the psql \dD output to not show not-null constraints in the column "Check", since it's already shown in the column "Nullable". This has also been off since e5da0fe3c22. Reviewed-by: jian he <jian.universality@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/9ec24d7b-633d-463a-84c6-7acff769c9e8%40eisentraut.org
* Fixup various StringInfo function usagesDavid Rowley2024-04-10
| | | | | | | | | | | | | | | This adjusts various appendStringInfo* function calls to use a more appropriate and efficient function with the same behavior. For example, use appendStringInfoChar() when appending a single character rather than appendStringInfo() and appendStringInfoString() when no formatting is required rather than using appendStringInfo(). All adjustments made here are in code that's new to v17, so it makes sense to fix these now rather than wait a few years and make backpatching harder. Discussion: https://postgr.es/m/CAApHDvojY2UvMiO+9_55ArTj10P1LBNJyyoGB+C65BLDNT0GsQ@mail.gmail.com Reviewed-by: Nathan Bossart, Tom Lane
* JSON_TABLE: Add support for NESTED paths and columnsAmit Langote2024-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A NESTED path allows to extract data from nested levels of JSON objects given by the parent path expression, which are projected as columns specified using a nested COLUMNS clause, just like the parent COLUMNS clause. Rows comprised from a NESTED columns are "joined" to the row comprised from the parent columns. If a particular NESTED path evaluates to 0 rows, then the nested COLUMNS will emit NULLs, making it an OUTER join. NESTED columns themselves may include NESTED paths to allow extracting data from arbitrary nesting levels, which are likewise joined against the rows at the parent level. Multiple NESTED paths at a given level are called "sibling" paths and their rows are combined by UNIONing them, that is, after being joined against the parent row as described above. Author: Nikita Glukhov <n.gluhov@postgrespro.ru> Author: Teodor Sigaev <teodor@sigaev.ru> Author: Oleg Bartunov <obartunov@gmail.com> Author: Alexander Korotkov <aekorotkov@gmail.com> Author: Andrew Dunstan <andrew@dunslane.net> Author: Amit Langote <amitlangote09@gmail.com> Author: Jian He <jian.universality@gmail.com> Reviewers have included (in no particular order): Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu, Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby, Álvaro Herrera, Jian He Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com
* Fix JsonExpr deparsing to emit QUOTES and WRAPPER correctlyAmit Langote2024-04-08
| | | | | | | | | | | | | | | Currently, get_json_expr_options() does not emit the default values for QUOTES (KEEP QUOTES) and WRAPPER (WITHOUT WRAPPER). That causes the deparsed JSON_TABLE() columns, such as those contained in a a view's query, to behave differently when executed than the original definition. That's because the rules encoded in transformJsonTableColumns() will choose either JSON_VALUE() or JSON_QUERY() as implementation to execute a given column's path expression depending on the QUOTES and WRAPPER specificationd and they have slightly different semantics. Reported-by: Jian He <jian.universality@gmail.com> Discussion: https://postgr.es/m/CACJufxEqhqsfrg_p7EMyo5zak3d767iFDL8vz_4%3DZBHpOtrghw%40mail.gmail.com
* Implement ALTER TABLE ... SPLIT PARTITION ... commandAlexander Korotkov2024-04-07
| | | | | | | | | | | | | | | | | | | | This new DDL command splits a single partition into several parititions. Just like ALTER TABLE ... MERGE PARTITIONS ... command, new patitions are created using createPartitionTable() function with parent partition as the template. This commit comprises quite naive implementation which works in single process and holds the ACCESS EXCLUSIVE LOCK on the parent table during all the operations including the tuple routing. This is why this new DDL command can't be recommended for large partitioned tables under a high load. However, this implementation come in handy in certain cases even as is. Also, it could be used as a foundation for future implementations with lesser locking and possibly parallel. Discussion: https://postgr.es/m/c73a1746-0cd0-6bdd-6b23-3ae0b7c0c582%40postgrespro.ru Author: Dmitry Koval Reviewed-by: Matthias van de Meent, Laurenz Albe, Zhihong Yu, Justin Pryzby Reviewed-by: Alvaro Herrera, Robert Haas, Stephane Tachoires
* Add basic JSON_TABLE() functionalityAmit Langote2024-04-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | JSON_TABLE() allows JSON data to be converted into a relational view and thus used, for example, in a FROM clause, like other tabular data. Data to show in the view is selected from a source JSON object using a JSON path expression to get a sequence of JSON objects that's called a "row pattern", which becomes the source to compute the SQL/JSON values that populate the view's output columns. Column values themselves are computed using JSON path expressions applied to each of the JSON objects comprising the "row pattern", for which the SQL/JSON query functions added in 6185c9737cf4 are used. To implement JSON_TABLE() as a table function, this augments the TableFunc and TableFuncScanState nodes that are currently used to support XMLTABLE() with some JSON_TABLE()-specific fields. Note that the JSON_TABLE() spec includes NESTED COLUMNS and PLAN clauses, which are required to provide more flexibility to extract data out of nested JSON objects, but they are not implemented here to keep this commit of manageable size. Author: Nikita Glukhov <n.gluhov@postgrespro.ru> Author: Teodor Sigaev <teodor@sigaev.ru> Author: Oleg Bartunov <obartunov@gmail.com> Author: Alexander Korotkov <aekorotkov@gmail.com> Author: Andrew Dunstan <andrew@dunslane.net> Author: Amit Langote <amitlangote09@gmail.com> Author: Jian He <jian.universality@gmail.com> Reviewers have included (in no particular order): Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu, Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby, Álvaro Herrera, Jian He Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com
* Add support for MERGE ... WHEN NOT MATCHED BY SOURCE.Dean Rasheed2024-03-30
| | | | | | | | | | | | | | | | | | | This allows MERGE commands to include WHEN NOT MATCHED BY SOURCE actions, which operate on rows that exist in the target relation, but not in the data source. These actions can execute UPDATE, DELETE, or DO NOTHING sub-commands. This is in contrast to already-supported WHEN NOT MATCHED actions, which operate on rows that exist in the data source, but not in the target relation. To make this distinction clearer, such actions may now be written as WHEN NOT MATCHED BY TARGET. Writing WHEN NOT MATCHED without specifying BY SOURCE or BY TARGET is equivalent to writing WHEN NOT MATCHED BY TARGET. Dean Rasheed, reviewed by Alvaro Herrera, Ted Yu and Vik Fearing. Discussion: https://postgr.es/m/CAEZATCWqnKGc57Y_JanUBHQXNKcXd7r=0R4NEZUVwP+syRkWbA@mail.gmail.com
* Add temporal FOREIGN KEY contraintsPeter Eisentraut2024-03-24
| | | | | | | | | | | | | | | | | | Add PERIOD clause to foreign key constraint definitions. This is supported for range and multirange types. Temporal foreign keys check for range containment instead of equality. This feature matches the behavior of the SQL standard temporal foreign keys, but it works on PostgreSQL's native ranges instead of SQL's "periods", which don't exist in PostgreSQL (yet). Reference actions ON {UPDATE,DELETE} {CASCADE,SET NULL,SET DEFAULT} are not supported yet. Author: Paul A. Jungwirth <pj@illuminatedcomputing.com> Reviewed-by: Peter Eisentraut <peter@eisentraut.org> Reviewed-by: jian he <jian.universality@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
* Add SQL/JSON query functionsAmit Langote2024-03-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This introduces the following SQL/JSON functions for querying JSON data using jsonpath expressions: JSON_EXISTS(), which can be used to apply a jsonpath expression to a JSON value to check if it yields any values. JSON_QUERY(), which can be used to to apply a jsonpath expression to a JSON value to get a JSON object, an array, or a string. There are various options to control whether multi-value result uses array wrappers and whether the singleton scalar strings are quoted or not. JSON_VALUE(), which can be used to apply a jsonpath expression to a JSON value to return a single scalar value, producing an error if it multiple values are matched. Both JSON_VALUE() and JSON_QUERY() functions have options for handling EMPTY and ERROR conditions, which can be used to specify the behavior when no values are matched and when an error occurs during jsonpath evaluation, respectively. Author: Nikita Glukhov <n.gluhov@postgrespro.ru> Author: Teodor Sigaev <teodor@sigaev.ru> Author: Oleg Bartunov <obartunov@gmail.com> Author: Alexander Korotkov <aekorotkov@gmail.com> Author: Andrew Dunstan <andrew@dunslane.net> Author: Amit Langote <amitlangote09@gmail.com> Author: Peter Eisentraut <peter@eisentraut.org> Author: Jian He <jian.universality@gmail.com> Reviewers have included (in no particular order): Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu, Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby, Álvaro Herrera, Jian He, Anton A. Melnikov, Nikita Malakhov, Peter Eisentraut, Tomas Vondra Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org Discussion: https://postgr.es/m/CA+HiwqHROpf9e644D8BRqYvaAPmgBZVup-xKMDPk-nd4EpgzHw@mail.gmail.com Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com
* Catalog domain not-null constraintsPeter Eisentraut2024-03-20
| | | | | | | | | | This applies the explicit catalog representation of not-null constraints introduced by b0e96f3119 for table constraints also to domain not-null constraints. Reviewed-by: Aleksander Alekseev <aleksander@timescale.com> Reviewed-by: jian he <jian.universality@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/9ec24d7b-633d-463a-84c6-7acff769c9e8%40eisentraut.org
* Improve EXPLAIN's display of SubPlan nodes and output parameters.Tom Lane2024-03-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Historically we've printed SubPlan expression nodes as "(SubPlan N)", which is pretty uninformative. Trying to reproduce the original SQL for the subquery is still as impractical as before, and would be mighty verbose as well. However, we can still do better than that. Displaying the "testexpr" when present, and adding a keyword to indicate the SubLinkType, goes a long way toward showing what's really going on. In addition, this patch gets rid of EXPLAIN's use of "$n" to represent subplan and initplan output Params. Instead we now print "(SubPlan N).colX" or "(InitPlan N).colX" to represent the X'th output column of that subplan. This eliminates confusion with the use of "$n" to represent PARAM_EXTERN Params, and it's useful for the first part of this change because it eliminates needing some other indication of which subplan is referenced by a SubPlan that has a testexpr. In passing, this adds simple regression test coverage of the ROWCOMPARE_SUBLINK code paths, which were entirely unburdened by testing before. Tom Lane and Dean Rasheed, reviewed by Aleksander Alekseev. Thanks to Chantal Keller for raising the question of whether this area couldn't be improved. Discussion: https://postgr.es/m/2838538.1705692747@sss.pgh.pa.us
* Add RETURNING support to MERGE.Dean Rasheed2024-03-17
| | | | | | | | | | | | | | | | | | | | | | | | | | This allows a RETURNING clause to be appended to a MERGE query, to return values based on each row inserted, updated, or deleted. As with plain INSERT, UPDATE, and DELETE commands, the returned values are based on the new contents of the target table for INSERT and UPDATE actions, and on its old contents for DELETE actions. Values from the source relation may also be returned. As with INSERT/UPDATE/DELETE, the output of MERGE ... RETURNING may be used as the source relation for other operations such as WITH queries and COPY commands. Additionally, a special function merge_action() is provided, which returns 'INSERT', 'UPDATE', or 'DELETE', depending on the action executed for each row. The merge_action() function can be used anywhere in the RETURNING list, including in arbitrary expressions and subqueries, but it is an error to use it anywhere outside of a MERGE query's RETURNING list. Dean Rasheed, reviewed by Isaac Morland, Vik Fearing, Alvaro Herrera, Gurjeet Singh, Jian He, Jeff Davis, Merlin Moncure, Peter Eisentraut, and Wolfgang Walther. Discussion: http://postgr.es/m/CAEZATCWePEGQR5LBn-vD6SfeLZafzEm2Qy_L_Oky2=qw2w3Pzg@mail.gmail.com
* Fix EXPLAIN output for subplans in MERGE.Dean Rasheed2024-03-17
| | | | | | | | | | | | | | | | | | Given a subplan in a MERGE query, EXPLAIN would sometimes fail to properly display expressions involving Params referencing variables in other parts of the plan tree. This would affect subplans outside the topmost join plan node, for which expansion of Params would go via the top-level ModifyTable plan node. The problem was that "inner_tlist" for the ModifyTable node's deparse_namespace was set to the join node's targetlist, but "inner_plan" was set to the ModifyTable node itself, rather than the join node, leading to incorrect results when descending to the referenced variable. Fix and backpatch to v15, where MERGE was introduced. Discussion: https://postgr.es/m/CAEZATCWAv-sZuH%2BwG5xJ-%2BGt7qGNGX8wUQd3XYydMFDKgRB9nw%40mail.gmail.com
* Rename pg_constraint.conwithoutoverlaps to conperiodPeter Eisentraut2024-03-05
| | | | | | | | | | | | | | | | | pg_constraint.conwithoutoverlaps was recently added to support primary keys and unique constraints with the WITHOUT OVERLAPS clause. An upcoming patch provides the foreign-key side of this functionality, but the syntax there is different and uses the keyword PERIOD. It would make sense to use the same pg_constraint field for both of these, but then we should pick a more general name that conveys "this constraint has a temporal/period-related feature". conperiod works for that and is nicely compact. Changing this now avoids possibly having to introduce versioning into clients. Note there are still some "without overlaps" variables left, which deal specifically with the parsing of the primary key/unique constraint feature. Author: Paul A. Jungwirth <pj@illuminatedcomputing.com> Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
* Remove unused #include's from backend .c filesPeter Eisentraut2024-03-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | as determined by include-what-you-use (IWYU) While IWYU also suggests to *add* a bunch of #include's (which is its main purpose), this patch does not do that. In some cases, a more specific #include replaces another less specific one. Some manual adjustments of the automatic result: - IWYU currently doesn't know about includes that provide global variable declarations (like -Wmissing-variable-declarations), so those includes are being kept manually. - All includes for port(ability) headers are being kept for now, to play it safe. - No changes of catalog/pg_foo.h to catalog/pg_foo_d.h, to keep the patch from exploding in size. Note that this patch touches just *.c files, so nothing declared in header files changes in hidden ways. As a small example, in src/backend/access/transam/rmgr.c, some IWYU pragma annotations are added to handle a special case there. Discussion: https://www.postgresql.org/message-id/flat/af837490-6b2f-46df-ba05-37ea6a6653fc%40eisentraut.org
* Remove race condition in pg_get_expr().Tom Lane2024-02-09
| | | | | | | | | | | | | | | | | | | | | | | Since its introduction, pg_get_expr() has intended to silently return NULL if called with an invalid relation OID, as can happen when scanning the catalogs concurrently with relation drops. However, there is a race condition: we check validity of the OID at the start, but it could get dropped just afterward, leading to failures. This is the cause of some intermittent instability we're seeing in a proposed new test case, and presumably it's a hazard in the field as well. We can fix this by AccessShareLock-ing the target relation for the duration of pg_get_expr(). Since we don't require any permissions on the target relation, this is semantically a bit undesirable. But it turns out that the set_relation_column_names() subroutine already takes a transient AccessShareLock on that relation, and has done since commit 2ffa740be in 2012. Given the lack of complaints about that, it seems like there should be no harm in holding the lock a bit longer. Back-patch to all supported branches. Discussion: https://postgr.es/m/31ddcc01-a71b-4e8c-9948-01d1c47293ca@eisentraut.org
* Add temporal PRIMARY KEY and UNIQUE constraintsPeter Eisentraut2024-01-24
| | | | | | | | | | | | Add WITHOUT OVERLAPS clause to PRIMARY KEY and UNIQUE constraints. These are backed by GiST indexes instead of B-tree indexes, since they are essentially exclusion constraints with = for the scalar parts of the key and && for the temporal part. Author: Paul A. Jungwirth <pj@illuminatedcomputing.com> Reviewed-by: Peter Eisentraut <peter@eisentraut.org> Reviewed-by: jian he <jian.universality@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
* Update copyright for 2024Bruce Momjian2024-01-03
| | | | | | | | Reported-by: Michael Paquier Discussion: https://postgr.es/m/ZZKTDPxBBMt3C0J9@paquier.xyz Backpatch-through: 12
* Add support for AT LOCALMichael Paquier2023-10-13
| | | | | | | | | | | | | | | When converting a timestamp to/from with/without time zone, the SQL Standard specifies an AT LOCAL variant of AT TIME ZONE which uses the session's time zone. This includes three system functions able to do the work in the same way as the existing flavors for AT TIME ZONE, except that these need to be marked as stable as they depend on the session's TimeZone GUC. Bump catalog version. Author: Vik Fearing Reviewed-by: Laurenz Albe, Cary Huang, Michael Paquier Discussion: https://postgr.es/m/8e25dec4-5667-c1a5-6581-167d710c2182@postgresfriends.org
* Tidy-up some appendStringInfo*() usagesDavid Rowley2023-10-03
| | | | | | | | | | | | Make a few newish calls to appendStringInfo() which have no special formatting use appendStringInfoString() instead. Also, adjust usages of appendStringInfoString() which only append a string containing a single character to make use of appendStringInfoChar() instead. This makes the code marginally faster, but primarily this change is so we use the StringInfo type as it was intended to be used. Discussion: https://postgr.es/m/CAApHDvpXKQmL+r=VDNS98upqhr9yGBhv2Jw3GBFFk_wKHcB39A@mail.gmail.com
* Add some const qualifiersPeter Eisentraut2023-09-26
| | | | | | | | | | | There was a mismatch between the const qualifiers for excludeDirContents in src/backend/backup/basebackup.c and src/bin/pg_rewind/filemap.c, which led to a quick search for similar cases. We should make excludeDirContents match, but the rest of the changes seem like a good idea as well. Author: David Steele <david@pgmasters.net> Discussion: https://www.postgresql.org/message-id/flat/669a035c-d23d-2f38-7ff0-0cb93e01d610@pgmasters.net
* Track nesting depth correctly when drilling down into RECORD Vars.Tom Lane2023-09-15
| | | | | | | | | | | | | | | | | | expandRecordVariable() failed to adjust the parse nesting structure correctly when recursing to inspect an outer-level Var. This could result in assertion failures or core dumps in corner cases. Likewise, get_name_for_var_field() failed to adjust the deparse namespace stack correctly when recursing to inspect an outer-level Var. In this case the likely result was a "bogus varno" error while deparsing a view. Per bug #18077 from Jingzhou Fu. Back-patch to all supported branches. Richard Guo, with some adjustments by me Discussion: https://postgr.es/m/18077-b9db97c6e0ab45d8@postgresql.org
* Catalog not-null constraintsAlvaro Herrera2023-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We now create contype='n' pg_constraint rows for not-null constraints. We propagate these constraints to other tables during operations such as adding inheritance relationships, creating and attaching partitions and creating tables LIKE other tables. We also spawn not-null constraints for inheritance child tables when their parents have primary keys. These related constraints mostly follow the well-known rules of conislocal and coninhcount that we have for CHECK constraints, with some adaptations: for example, as opposed to CHECK constraints, we don't match not-null ones by name when descending a hierarchy to alter it, instead matching by column name that they apply to. This means we don't require the constraint names to be identical across a hierarchy. For now, we omit them for system catalogs. Maybe this is worth reconsidering. We don't support NOT VALID nor DEFERRABLE clauses either; these can be added as separate features later (this patch is already large and complicated enough.) psql shows these constraints in \d+. pg_dump requires some ad-hoc hacks, particularly when dumping a primary key. We now create one "throwaway" not-null constraint for each column in the PK together with the CREATE TABLE command, and once the PK is created, all those throwaway constraints are removed. This avoids having to check each tuple for nullness when the dump restores the primary key creation. pg_upgrading from an older release requires a somewhat brittle procedure to create a constraint state that matches what would be created if the database were being created fresh in Postgres 17. I have tested all the scenarios I could think of, and it works correctly as far as I can tell, but I could have neglected weird cases. This patch has been very long in the making. The first patch was written by Bernd Helmle in 2010 to add a new pg_constraint.contype value ('n'), which I (Álvaro) then hijacked in 2011 and 2012, until that one was killed by the realization that we ought to use contype='c' instead: manufactured CHECK constraints. However, later SQL standard development, as well as nonobvious emergent properties of that design (mostly, failure to distinguish them from "normal" CHECK constraints as well as the performance implication of having to test the CHECK expression) led us to reconsider this choice, so now the current implementation uses contype='n' again. During Postgres 16 this had already been introduced by commit e056c557aef4, but there were some problems mainly with the pg_upgrade procedure that couldn't be fixed in reasonable time, so it was reverted. In 2016 Vitaly Burovoy also worked on this feature[1] but found no consensus for his proposed approach, which was claimed to be closer to the letter of the standard, requiring an additional pg_attribute column to track the OID of the not-null constraint for that column. [1] https://postgr.es/m/CAKOSWNkN6HSyatuys8xZxzRCR-KL1OkHS5-b9qd9bf1Rad3PLA@mail.gmail.com Author: Álvaro Herrera <alvherre@alvh.no-ip.org> Author: Bernd Helmle <mailings@oopsware.de> Reviewed-by: Justin Pryzby <pryzby@telsasoft.com> Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com> Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
* Add more SQL/JSON constructor functionsAmit Langote2023-07-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This Patch introduces three SQL standard JSON functions: JSON() JSON_SCALAR() JSON_SERIALIZE() JSON() produces json values from text, bytea, json or jsonb values, and has facilitites for handling duplicate keys. JSON_SCALAR() produces a json value from any scalar sql value, including json and jsonb. JSON_SERIALIZE() produces text or bytea from input which containis or represents json or jsonb; For the most part these functions don't add any significant new capabilities, but they will be of use to users wanting standard compliant JSON handling. Catversion bumped as this changes ruleutils.c. Author: Nikita Glukhov <n.gluhov@postgrespro.ru> Author: Teodor Sigaev <teodor@sigaev.ru> Author: Oleg Bartunov <obartunov@gmail.com> Author: Alexander Korotkov <aekorotkov@gmail.com> Author: Andrew Dunstan <andrew@dunslane.net> Author: Amit Langote <amitlangote09@gmail.com> Reviewers have included (in no particular order) Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu, Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby, Álvaro Herrera, Peter Eisentraut Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com
* Add missing ObjectIdGetDatum() in syscache lookup calls for OidsMichael Paquier2023-07-20
| | | | | | | | | | Based on how postgres.h foes the Oid <-> Datum conversion, there is no existing bugs but let's be consistent. 17 spots have been noticed as incorrectly passing down Oids rather than Datums. Aleksander got one, Zhang two and I the rest. Author: Michael Paquier, Aleksander Alekseev, Zhang Mingli Discussion: https://postgr.es/m/ZLUhqsqQN1MOaxdw@paquier.xyz
* Pre-beta mechanical code beautification.Tom Lane2023-05-19
| | | | | | | | | | | | | | | Run pgindent, pgperltidy, and reformat-dat-files. This set of diffs is a bit larger than typical. We've updated to pg_bsd_indent 2.1.2, which properly indents variable declarations that have multi-line initialization expressions (the continuation lines are now indented one tab stop). We've also updated to perltidy version 20230309 and changed some of its settings, which reduces its desire to add whitespace to lines to make assignments etc. line up. Going forward, that should make for fewer random-seeming changes to existing code. Discussion: https://postgr.es/m/20230428092545.qfb3y5wcu4cm75ur@alvherre.pgsql
* pageinspect: Fix gist_page_items() with included columnsMichael Paquier2023-05-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Non-leaf pages of GiST indexes contain key attributes, leaf pages contain both key and non-key attributes, and gist_page_items() ignored the handling of non-key attributes. This caused a few problems when using gist_page_items() on a GiST index with INCLUDE: - On a non-leaf page, the function would crash. - On a leaf page, the function would work, but miss to display all the values for included attributes. This commit fixes gist_page_items() to handle such cases in a more appropriate way, and now displays the values of key and non-key attributes for each item separately in a style consistent with what ruleutils.c would generate for the attribute list, depending on the page type dealt with. In a way similar to how a record is displayed, values would be double-quoted for key or non-key attributes if required. ruleutils.c did not provide a routine able to control if non-key attributes should be displayed, so an extended() routine for index definitions is added to work around the leaf and non-leaf page differences. While on it, this commit fixes a third problem related to the amount of data reported for key attributes. The code originally relied on BuildIndexValueDescription() (used for error reports on constraints) that would not print all the data stored in the index but the index opclass's input type, so this limited the amount of information available. This switch makes gist_page_items() much cheaper as there is no need to run ACL checks for each item printed, which is not an issue anyway as superuser rights are required to execute the functions of pageinspect. Opclasses whose data cannot be displayed can rely on gist_page_items_bytea(). The documentation of this function was slightly incorrect for the output results generated on HEAD and v15, so adjust it on these branches. Author: Alexander Lakhin, Michael Paquier Discussion: https://postgr.es/m/17884-cb8c326522977acb@postgresql.org Backpatch-through: 14
* Add back SQLValueFunction for SQL keywordsMichael Paquier2023-05-17
| | | | | | | | | | | | | | | | | | | | | | | | This is equivalent to a revert of f193883 and fb32748, with the addition that the declaration of the SQLValueFunction node needs to gain a couple of node_attr for query jumbling. The performance impact of removing the function call inlining is proving to be too huge for some workloads where these are used. A worst-case test case of involving only simple SELECT queries with a SQL keyword is proving to lead to a reduction of 10% in TPS via pgbench and prepared queries on a high-end machine. None of the tests I ran back for this set of changes saw such a huge gap, but Alexander Lakhin and Andres Freund have found that this can be noticeable. Keeping the older performance would mean to do more inlining in the executor when using COERCE_SQL_SYNTAX for a function expression, similarly to what SQLValueFunction does. This requires more redesign work and there is little time until 16beta1 is released, so for now reverting the change is the best way forward, bringing back the previous performance. Bump catalog version. Reported-by: Alexander Lakhin Discussion: https://postgr.es/m/b32bed1b-0746-9b20-1472-4bdc9ca66d52@gmail.com
* Add ruleutils support for decompiling MERGE commands.Tom Lane2023-05-07
| | | | | | | | | This was overlooked when MERGE was added, but it's essential support for MERGE in new-style SQL functions. Alvaro Herrera Discussion: https://postgr.es/m/3579737.1683293801@sss.pgh.pa.us
* Revert "Catalog NOT NULL constraints" and falloutAlvaro Herrera2023-04-12
| | | | | | | | | | | This reverts commit e056c557aef4 and minor later fixes thereof. There's a few problems in this new feature -- most notably regarding pg_upgrade behavior, but others as well. This new feature is not in any way critical on its own, so instead of scrambling to fix it we revert it and try again in early 17 with these issues in mind. Discussion: https://postgr.es/m/3801207.1681057430@sss.pgh.pa.us
* Catalog NOT NULL constraintsAlvaro Herrera2023-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We now create pg_constaint rows for NOT NULL constraints with contype='n'. We propagate these constraints during operations such as adding inheritance relationships, creating and attaching partitions, creating tables LIKE other tables. We mostly follow the well-known rules of conislocal and coninhcount that we have for CHECK constraints, with some adaptations; for example, as opposed to CHECK constraints, we don't match NOT NULL ones by name when descending a hierarchy to alter it; instead we match by column number. This means we don't require the constraint names to be identical across a hierarchy. For now, we omit them from system catalogs. Maybe this is worth reconsidering. We don't support NOT VALID nor DEFERRABLE clauses either; these can be added as separate features later (this patch is already large and complicated enough.) This has been very long in the making. The first patch was written by Bernd Helmle in 2010 to add a new pg_constraint.contype value ('n'), which I (Álvaro) then hijacked in 2011 and 2012, until that one was killed by the realization that we ought to use contype='c' instead: manufactured CHECK constraints. However, later SQL standard development, as well as nonobvious emergent properties of that design (mostly, failure to distinguish them from "normal" CHECK constraints as well as the performance implication of having to test the CHECK expression) led us to reconsider this choice, so now the current implementation uses contype='n' again. In 2016 Vitaly Burovoy also worked on this feature[1] but found no consensus for his proposed approach, which was claimed to be closer to the letter of the standard, requiring additional pg_attribute columns to track the OID of the NOT NULL constraint for that column. [1] https://postgr.es/m/CAKOSWNkN6HSyatuys8xZxzRCR-KL1OkHS5-b9qd9bf1Rad3PLA@mail.gmail.com Author: Álvaro Herrera <alvherre@alvh.no-ip.org> Author: Bernd Helmle <mailings@oopsware.de> Reviewed-by: Justin Pryzby <pryzby@telsasoft.com> Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com> Discussion: https://postgr.es/m/CACA0E642A0267EDA387AF2B%40%5B172.26.14.62%5D Discussion: https://postgr.es/m/AANLkTinLXMOEMz+0J29tf1POokKi4XDkWJ6-DDR9BKgU@mail.gmail.com Discussion: https://postgr.es/m/20110707213401.GA27098@alvh.no-ip.org Discussion: https://postgr.es/m/1343682669-sup-2532@alvh.no-ip.org Discussion: https://postgr.es/m/CAKOSWNkN6HSyatuys8xZxzRCR-KL1OkHS5-b9qd9bf1Rad3PLA@mail.gmail.com Discussion: https://postgr.es/m/20220817181249.q7qvj3okywctra3c@alvherre.pgsql
* SQL/JSON: support the IS JSON predicateAlvaro Herrera2023-03-31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces the SQL standard IS JSON predicate. It operates on text and bytea values representing JSON, as well as on the json and jsonb types. Each test has IS and IS NOT variants and supports a WITH UNIQUE KEYS flag. The tests are: IS JSON [VALUE] IS JSON ARRAY IS JSON OBJECT IS JSON SCALAR These should be self-explanatory. The WITH UNIQUE KEYS flag makes these return false when duplicate keys exist in any object within the value, not necessarily directly contained in the outermost object. Author: Nikita Glukhov <n.gluhov@postgrespro.ru> Author: Teodor Sigaev <teodor@sigaev.ru> Author: Oleg Bartunov <obartunov@gmail.com> Author: Alexander Korotkov <aekorotkov@gmail.com> Author: Amit Langote <amitlangote09@gmail.com> Author: Andrew Dunstan <andrew@dunslane.net> Reviewers have included (in no particular order) Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu, Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby. Discussion: https://postgr.es/m/CAF4Au4w2x-5LTnN_bxky-mq4=WOqsGsxSpENCzHRAzSnEd8+WQ@mail.gmail.com Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org