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path: root/src/backend/executor/execExpr.c
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2024-10-20SQL/JSON: Fix some oversights in commit b6e1157e7Amit Langote
The decision in b6e1157e7 to ignore raw_expr when evaluating a JsonValueExpr was incorrect. While its value is not ultimately used (since formatted_expr's value is), failing to initialize it can lead to problems, for instance, when the expression tree in raw_expr contains Aggref nodes, which must be initialized to ensure the parent Agg node works correctly. Also, optimize eval_const_expressions_mutator()'s handling of JsonValueExpr a bit. Currently, when formatted_expr cannot be folded into a constant, we end up processing it twice -- once directly in eval_const_expressions_mutator() and again recursively via ece_generic_processing(). This recursive processing is required to handle raw_expr. To avoid the redundant processing of formatted_expr, we now process raw_expr directly in eval_const_expressions_mutator(). Finally, update the comment of JsonValueExpr to describe the roles of raw_expr and formatted_expr more clearly. Bug: #18657 Reported-by: Alexander Lakhin <exclusion@gmail.com> Diagnosed-by: Fabio R. Sluzala <fabio3rs@gmail.com> Diagnosed-by: Tender Wang <tndrwang@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/18657-1b90ccce2b16bdb8@postgresql.org Backpatch-through: 16
2024-10-17Don't store intermediate hash values in ExprState->resvalueDavid Rowley
adf97c156 made it so ExprStates could support hashing and changed Hash Join to use that instead of manually extracting Datums from tuples and hashing them one column at a time. When hashing multiple columns or expressions, the code added in that commit stored the intermediate hash value in the ExprState's resvalue field. That was a mistake as steps may be injected into the ExprState between each hashing step that look at or overwrite the stored intermediate hash value. EEOP_PARAM_SET is an example of such a step. Here we fix this by adding a new dedicated field for storing intermediate hash values and adjust the code so that all apart from the final hashing step store their result in the intermediate field. In passing, rename a variable so that it's more aligned to the surrounding code and also so a few lines stay within the 80 char margin. Reported-by: Andres Freund Reviewed-by: Alena Rybakina <a.rybakina@postgrespro.ru> Discussion: https://postgr.es/m/CAApHDvqo9eenEFXND5zZ9JxO_k4eTA4jKMGxSyjdTrsmYvnmZw@mail.gmail.com
2024-09-09SQL/JSON: Avoid initializing unnecessary ON ERROR / ON EMPTY stepsAmit Langote
When the ON ERROR / ON EMPTY behavior is to return NULL, returning NULL directly from ExecEvalJsonExprPath() suffices. Therefore, there's no need to create separate steps to check the error/empty flag or those to evaluate the the constant NULL expression. This speeds up common cases because the default ON ERROR / ON EMPTY behavior for JSON_QUERY() and JSON_VALUE() is to return NULL. However, these steps are necessary if the RETURNING type is a domain, as constraints on the domain may need to be checked. Reported-by: Jian He <jian.universality@gmail.com> Author: Jian He <jian.universality@gmail.com> Author: Amit Langote <amitlangote09@gmail.com> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
2024-09-06Revert recent SQL/JSON related commitsAmit Langote
Reverts 68222851d5a8, 565caaa79af, and 3a97460970f, because a few BF animals didn't like one or all of them.
2024-09-06SQL/JSON: Avoid initializing unnecessary ON ERROR / ON EMPTY stepsAmit Langote
When the ON ERROR / ON EMPTY behavior is to return NULL, returning NULL directly from ExecEvalJsonExprPath() suffices. Therefore, there's no need to create separate steps to check the error/empty flag or those to evaluate the the constant NULL expression. This speeds up common cases because the default ON ERROR / ON EMPTY behavior for JSON_QUERY() and JSON_VALUE() is to return NULL. However, these steps are necessary if the RETURNING type is a domain, as constraints on the domain may need to be checked. Reported-by: Jian He <jian.universality@gmail.com> Author: Jian He <jian.universality@gmail.com> Author: Amit Langote <amitlangote09@gmail.com> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
2024-08-20Speed up Hash Join by making ExprStates support hashingDavid Rowley
Here we add ExprState support for obtaining a 32-bit hash value from a list of expressions. This allows both faster hashing and also JIT compilation of these expressions. This is especially useful when hash joins have multiple join keys as the previous code called ExecEvalExpr on each hash join key individually and that was inefficient as tuple deformation would have only taken into account one key at a time, which could lead to walking the tuple once for each join key. With the new code, we'll determine the maximum attribute required and deform the tuple to that point only once. Some performance tests done with this change have shown up to a 20% performance increase of a query containing a Hash Join without JIT compilation and up to a 26% performance increase when JIT is enabled and optimization and inlining were performed by the JIT compiler. The performance increase with 1 join column was less with a 14% increase with and without JIT. This test was done using a fairly small hash table and a large number of hash probes. The increase will likely be less with large tables, especially ones larger than L3 cache as memory pressure is more likely to be the limiting factor there. This commit only addresses Hash Joins, but lays expression evaluation and JIT compilation infrastructure for other hashing needs such as Hash Aggregate. Author: David Rowley Reviewed-by: Alexey Dvoichenkov <alexey@hyperplane.net> Reviewed-by: Tels <nospam-pg-abuse@bloodgate.com> Discussion: https://postgr.es/m/CAApHDvoexAxgQFNQD_GRkr2O_eJUD1-wUGm%3Dm0L%2BGc%3DT%3DkEa4g%40mail.gmail.com
2024-07-31Evaluate arguments of correlated SubPlans in the referencing ExprStateAndres Freund
Until now we generated an ExprState for each parameter to a SubPlan and evaluated them one-by-one ExecScanSubPlan. That's sub-optimal as creating lots of small ExprStates a) makes JIT compilation more expensive b) wastes memory c) is a bit slower to execute This commit arranges to evaluate parameters to a SubPlan as part of the ExprState referencing a SubPlan, using the new EEOP_PARAM_SET expression step. We emit one EEOP_PARAM_SET for each argument to a subplan, just before the EEOP_SUBPLAN step. It likely is worth using EEOP_PARAM_SET in other places as well, e.g. for SubPlan outputs, nestloop parameters and - more ambitiously - to get rid of ExprContext->domainValue/caseValue/ecxt_agg*. But that's for later. Author: Andres Freund <andres@anarazel.de> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Alena Rybakina <lena.ribackina@yandex.ru> Discussion: https://postgr.es/m/20230225214401.346ancgjqc3zmvek@awork3.anarazel.de
2024-07-30SQL/JSON: Fix casting for integer EXISTS columns in JSON_TABLEAmit Langote
The current method of coercing the boolean result value of JsonPathExists() to the target type specified for an EXISTS column, which is to call the type's input function via json_populate_type(), leads to an error when the target type is integer, because the integer input function doesn't recognize boolean literal values as valid. Instead use the boolean-to-integer cast function for coercion in that case so that using integer or domains thereof as type for EXISTS columns works. Note that coercion for ON ERROR values TRUE and FALSE already works like that because the parser creates a cast expression including the cast function, but the coercion of the actual result value is not handled by the parser. Tests by Jian He. Reported-by: Jian He <jian.universality@gmail.com> Author: Jian He <jian.universality@gmail.com> Author: Amit Langote <amitlangote09@gmail.com> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
2024-07-26SQL/JSON: Remove useless code in ExecInitJsonExpr()Amit Langote
The code was for adding an unconditional JUMP to the next step, which is unnecessary processing. Reported-by: Jian He <jian.universality@gmail.com> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
2024-07-26SQL/JSON: Fix error-handling of some JsonBehavior expressionsAmit Langote
To ensure that the errors of executing a JsonBehavior expression that is coerced in the parser are caught instead of being thrown directly, pass ErrorSaveContext to ExecInitExprRec() when initializing it. Also, add a EEOP_JSONEXPR_COERCION_FINISH step to handle the errors that are caught that way. Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
2024-06-28SQL/JSON: Always coerce JsonExpr result at runtimeAmit Langote
Instead of looking up casts at parse time for converting the result of JsonPath* query functions to the specified or the default RETURNING type, always perform the conversion at runtime using either the target type's input function or the function json_populate_type(). There are two motivations for this change: 1. json_populate_type() coerces to types with typmod such that any string values that exceed length limit cause an error instead of silent truncation, which is necessary to be standard-conforming. 2. It was possible to end up with a cast expression that doesn't support soft handling of errors causing bugs in the of handling ON ERROR clause. JsonExpr.coercion_expr which would store the cast expression is no longer necessary, so remove. Bump catversion because stored rules change because of the above removal. Reported-by: Alvaro Herrera <alvherre@alvh.no-ip.org> Reviewed-by: Jian He <jian.universality@gmail.com> Discussion: Discussion: https://postgr.es/m/202405271326.5a5rprki64aw%40alvherre.pgsql
2024-06-19SQL/JSON: Correct jsonpath variable name matchingAmit Langote
Previously, GetJsonPathVar() allowed a jsonpath expression to reference any prefix of a PASSING variable's name. For example, the following query would incorrectly work: SELECT JSON_QUERY(context_item, jsonpath '$xy' PASSING val AS xyz); The fix ensures that the length of the variable name mentioned in a jsonpath expression matches exactly with the name of the PASSING variable before comparing the strings using strncmp(). Reported-by: Alvaro Herrera (off-list) Discussion: https://postgr.es/m/CA+HiwqFGkLWMvELBH6E4SQ45qUHthgcRH6gCJL20OsYDRtFx_w@mail.gmail.com
2024-04-23Remove some unnecessary fields from executor nodes.Tom Lane
JsonExprState.input_finfo is only assigned to, never read, and it's really fairly useless since the value can be gotten out of the adjacent input_fcinfo field. Let's remove it before someone starts to depend on it. While here, also remove TidScanState.tss_htup and AggState.combinedproj, which are referenced nowhere. Those should have been removed by the commits that caused them to become disused, but were not. I don't think a catversion bump is necessary here, since plan trees are never stored on disk. Matthias van de Meent Discussion: https://postgr.es/m/CAEze2WjsY4d0TBymLNGK4zpttUcg_YZaTjyWz2VfDUV6YH8wXQ@mail.gmail.com
2024-04-18Fix typos and duplicate wordsDaniel Gustafsson
This fixes various typos, duplicated words, and tiny bits of whitespace mainly in code comments but also in docs. Author: Daniel Gustafsson <daniel@yesql.se> Author: Heikki Linnakangas <hlinnaka@iki.fi> Author: Alexander Lakhin <exclusion@gmail.com> Author: David Rowley <dgrowleyml@gmail.com> Author: Nazir Bilal Yavuz <byavuz81@gmail.com> Discussion: https://postgr.es/m/3F577953-A29E-4722-98AD-2DA9EFF2CBB8@yesql.se
2024-04-04Add basic JSON_TABLE() functionalityAmit Langote
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
2024-03-21Add SQL/JSON query functionsAmit Langote
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
2024-03-17Add RETURNING support to MERGE.Dean Rasheed
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
2024-03-04Remove unused #include's from backend .c filesPeter Eisentraut
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
2024-01-24Add soft error handling to some expression nodesAmit Langote
This adjusts the code for CoerceViaIO and CoerceToDomain expression nodes to handle errors softly. For CoerceViaIo, this adds a new ExprEvalStep opcode EEOP_IOCOERCE_SAFE, which is implemented in the new accompanying function ExecEvalCoerceViaIOSafe(). The only difference from EEOP_IOCOERCE's inline implementation is that the input function receives an ErrorSaveContext via the function's FunctionCallInfo.context, which it can use to handle errors softly. For CoerceToDomain, this simply entails replacing the ereport() in ExecEvalConstraintNotNull() and ExecEvalConstraintCheck() by errsave() passing it the ErrorSaveContext passed in the expression's ExprEvalStep. In both cases, the ErrorSaveContext to be used is passed by setting ExprState.escontext to point to it before calling ExecInitExprRec() on the expression tree whose errors are to be handled softly. Note that there's no functional change as of this commit as no call site of ExecInitExprRec() has been changed. This is intended for implementing new SQL/JSON expression nodes in future commits. Extracted from a much larger patch to add SQL/JSON query functions. 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, Jian He, 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+HiwqHROpf9e644D8BRqYvaAPmgBZVup-xKMDPk-nd4EpgzHw@mail.gmail.com Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com
2024-01-04Add macros for looping through a List without a ListCell.Nathan Bossart
Many foreach loops only use the ListCell pointer to retrieve the content of the cell, like so: ListCell *lc; foreach(lc, mylist) { int myint = lfirst_int(lc); ... } This commit adds a few convenience macros that automatically declare the loop variable and retrieve the current cell's contents. This allows us to rewrite the previous loop like this: foreach_int(myint, mylist) { ... } This commit also adjusts a few existing loops in order to add coverage for the new/adjusted macros. There is presently no plan to bulk update all foreach loops, as that could introduce a significant amount of back-patching pain. Instead, these macros are primarily intended for use in new code. Author: Jelte Fennema-Nio Reviewed-by: David Rowley, Alvaro Herrera, Vignesh C, Tom Lane Discussion: https://postgr.es/m/CAGECzQSwXKnxGwW1_Q5JE%2B8Ja20kyAbhBHO04vVrQsLcDciwXA%40mail.gmail.com
2024-01-03Update copyright for 2024Bruce Momjian
Reported-by: Michael Paquier Discussion: https://postgr.es/m/ZZKTDPxBBMt3C0J9@paquier.xyz Backpatch-through: 12
2023-10-02Revert "Add soft error handling to some expression nodes"Amit Langote
This reverts commit 7fbc75b26ed8ec70c729c5e7f8233896c54c900f. Looks like the LLVM additions may not be totally correct.
2023-10-02Add soft error handling to some expression nodesAmit Langote
This adjusts the expression evaluation code for CoerceViaIO and CoerceToDomain to handle errors softly if needed. For CoerceViaIo, this means using InputFunctionCallSafe(), which provides the option to handle errors softly, instead of calling the type input function directly. For CoerceToDomain, this simply entails replacing the ereport() in ExecEvalConstraintCheck() by errsave(). In both cases, the ErrorSaveContext to be used when evaluating the expression is stored by ExecInitExprRec() in the expression's struct in the expression's ExprEvalStep. The ErrorSaveContext is passed by setting ExprState.escontext to point to it when calling ExecInitExprRec() on the expression whose errors are to be handled softly. Note that no call site of ExecInitExprRec() has been changed in this commit, so there's no functional change. This is intended for implementing new SQL/JSON expression nodes in future commits that will use to it suppress errors that may occur during type coercions. Reviewed-by: Álvaro Herrera Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com
2023-07-26Add more SQL/JSON constructor functionsAmit Langote
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
2023-07-13Don't include CaseTestExpr in JsonValueExpr.formatted_exprAmit Langote
A CaseTestExpr is currently being put into JsonValueExpr.formatted_expr as placeholder for the result of evaluating JsonValueExpr.raw_expr, which in turn is evaluated separately. Though, there's no need for this indirection if raw_expr itself can be embedded into formatted_expr and evaluated as part of evaluating the latter, especially as there is no special reason to evaluate it separately. So this commit makes it so. As a result, JsonValueExpr.raw_expr no longer needs to be evaluated in ExecInterpExpr(), eval_const_exprs_mutator() etc. and is now only used for displaying the original "unformatted" expression in ruleutils.c. While at it, this also removes the function makeCaseTestExpr(), because the code in makeJsonConstructorExpr() looks more readable without it IMO and isn't used by anyone else either. Finally, a note is added in the comment above CaseTestExpr's definition that JsonConstructorExpr is also using it. Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com
2023-05-19Pre-beta mechanical code beautification.Tom Lane
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
2023-05-17Add back SQLValueFunction for SQL keywordsMichael Paquier
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
2023-04-15Fix assignment to array of domain over composite, redux.Tom Lane
Commit 3e310d837 taught isAssignmentIndirectionExpr() to look through CoerceToDomain nodes. That's not sufficient, because since commit 04fe805a1 it's been possible for the planner to simplify CoerceToDomain to RelabelType when the domain has no constraints to enforce. So we need to look through RelabelType too. Per bug #17897 from Alexander Lakhin. Although 3e310d837 was back-patched to v11, it seems sufficient to apply this change to v12 and later, since 04fe805a1 came in in v12. Dmitry Dolgov Discussion: https://postgr.es/m/17897-4216c546c3874044@postgresql.org
2023-03-31SQL/JSON: support the IS JSON predicateAlvaro Herrera
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
2023-03-29SQL/JSON: add standard JSON constructor functionsAlvaro Herrera
This commit introduces the SQL/JSON standard-conforming constructors for JSON types: JSON_ARRAY() JSON_ARRAYAGG() JSON_OBJECT() JSON_OBJECTAGG() Most of the functionality was already present in PostgreSQL-specific functions, but these include some new functionality such as the ability to skip or include NULL values, and to allow duplicate keys or throw error when they are found, as well as the standard specified syntax to specify output type and format. 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> 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
2023-02-25Fix MULTIEXPR_SUBLINK with partitioned target tables, yet again.Tom Lane
We already tried to fix this in commits 3f7323cbb et al (and follow-on fixes), but now it emerges that there are still unfixed cases; moreover, these cases affect all branches not only pre-v14. I thought we had eliminated all cases of making multiple clones of an UPDATE's target list when we nuked inheritance_planner. But it turns out we still do that in some partitioned-UPDATE cases, notably including INSERT ... ON CONFLICT UPDATE, because ExecInitPartitionInfo thinks it's okay to clone and modify the parent's targetlist. This fix is based on a suggestion from Andres Freund: let's stop abusing the ParamExecData.execPlan mechanism, which was only ever meant to handle initplans, and instead solve the execution timing problem by having the expression compiler move MULTIEXPR_SUBLINK steps to the front of their expression step lists. This is feasible because (a) all branches still in support compile the entire targetlist of an UPDATE into a single ExprState, and (b) we know that all MULTIEXPR_SUBLINKs do need to be evaluated --- none could be buried inside a CASE, for example. There is a minor semantics change concerning the order of execution of the MULTIEXPR's subquery versus other parts of the parent targetlist, but that seems like something we can get away with. By doing that, we no longer need to worry about whether different clones of a MULTIEXPR_SUBLINK share output Params; their usage of that data structure won't overlap. Per bug #17800 from Alexander Lakhin. Back-patch to all supported branches. In v13 and earlier, we can revert 3f7323cbb and follow-on fixes; however, I chose to keep the SubPlan.subLinkId field added in ccbb54c72. We don't need that anymore in the core code, but it's cheap enough to fill, and removing a plan node field in a minor release seems like it'd be asking for trouble. Andres Freund and Tom Lane Discussion: https://postgr.es/m/17800-ff90866b3906c964@postgresql.org
2023-01-02Update copyright for 2023Bruce Momjian
Backpatch-through: 11
2022-11-21Replace SQLValueFunction by COERCE_SQL_SYNTAXMichael Paquier
This switch impacts 9 patterns related to a SQL-mandated special syntax for function calls: - LOCALTIME [ ( typmod ) ] - LOCALTIMESTAMP [ ( typmod ) ] - CURRENT_TIME [ ( typmod ) ] - CURRENT_TIMESTAMP [ ( typmod ) ] - CURRENT_DATE Five new entries are added to pg_proc to compensate the removal of SQLValueFunction to provide backward-compatibility and making this change transparent for the end-user (for example for the attribute generated when a keyword is specified in a SELECT or in a FROM clause without an alias, or when specifying something else than an Iconst to the parser). The parser included a set of checks coming from the files in charge of holding the C functions used for the SQLValueFunction calls (as of transformSQLValueFunction()), which are now moved within each function's execution path, so this reduces the dependencies between the execution and the parsing steps. As of this change, all the SQL keywords use the same paths for their work, relying only on COERCE_SQL_SYNTAX. Like fb32748, no performance difference has been noticed, while the perf profiles get reduced with ExecEvalSQLValueFunction() gone. Bump catalog version. Reviewed-by: Corey Huinker, Ted Yu Discussion: https://postgr.es/m/YzaG3MoryCguUOym@paquier.xyz
2022-11-13Refactor aclcheck functionsPeter Eisentraut
Instead of dozens of mostly-duplicate pg_foo_aclcheck() functions, write one common function object_aclcheck() that can handle almost all of them. We already have all the information we need, such as which system catalog corresponds to which catalog table and which column is the ACL column. There are a few pg_foo_aclcheck() that don't work via the generic function and have special APIs, so those stay as is. I also changed most pg_foo_aclmask() functions to static functions, since they are not used outside of aclchk.c. Reviewed-by: Corey Huinker <corey.huinker@gmail.com> Reviewed-by: Antonin Houska <ah@cybertec.at> Discussion: https://www.postgresql.org/message-id/flat/95c30f96-4060-2f48-98b5-a4392d3b6066@enterprisedb.com
2022-09-01Revert SQL/JSON featuresAndrew Dunstan
The reverts the following and makes some associated cleanups: commit f79b803dc: Common SQL/JSON clauses commit f4fb45d15: SQL/JSON constructors commit 5f0adec25: Make STRING an unreserved_keyword. commit 33a377608: IS JSON predicate commit 1a36bc9db: SQL/JSON query functions commit 606948b05: SQL JSON functions commit 49082c2cc: RETURNING clause for JSON() and JSON_SCALAR() commit 4e34747c8: JSON_TABLE commit fadb48b00: PLAN clauses for JSON_TABLE commit 2ef6f11b0: Reduce running time of jsonb_sqljson test commit 14d3f24fa: Further improve jsonb_sqljson parallel test commit a6baa4bad: Documentation for SQL/JSON features commit b46bcf7a4: Improve readability of SQL/JSON documentation. commit 112fdb352: Fix finalization for json_objectagg and friends commit fcdb35c32: Fix transformJsonBehavior commit 4cd8717af: Improve a couple of sql/json error messages commit f7a605f63: Small cleanups in SQL/JSON code commit 9c3d25e17: Fix JSON_OBJECTAGG uniquefying bug commit a79153b7a: Claim SQL standard compliance for SQL/JSON features commit a1e7616d6: Rework SQL/JSON documentation commit 8d9f9634e: Fix errors in copyfuncs/equalfuncs support for JSON node types. commit 3c633f32b: Only allow returning string types or bytea from json_serialize commit 67b26703b: expression eval: Fix EEOP_JSON_CONSTRUCTOR and EEOP_JSONEXPR size. The release notes are also adjusted. Backpatch to release 15. Discussion: https://postgr.es/m/40d2c882-bcac-19a9-754d-4299e1d87ac7@postgresql.org
2022-08-02Improve performance of ORDER BY / DISTINCT aggregatesDavid Rowley
ORDER BY / DISTINCT aggreagtes have, since implemented in Postgres, been executed by always performing a sort in nodeAgg.c to sort the tuples in the current group into the correct order before calling the transition function on the sorted tuples. This was not great as often there might be an index that could have provided pre-sorted input and allowed the transition functions to be called as the rows come in, rather than having to store them in a tuplestore in order to sort them once all the tuples for the group have arrived. Here we change the planner so it requests a path with a sort order which supports the most amount of ORDER BY / DISTINCT aggregate functions and add new code to the executor to allow it to support the processing of ORDER BY / DISTINCT aggregates where the tuples are already sorted in the correct order. Since there can be many ORDER BY / DISTINCT aggregates in any given query level, it's very possible that we can't find an order that suits all of these aggregates. The sort order that the planner chooses is simply the one that suits the most aggregate functions. We take the most strictly sorted variation of each order and see how many aggregate functions can use that, then we try again with the order of the remaining aggregates to see if another order would suit more aggregate functions. For example: SELECT agg(a ORDER BY a),agg2(a ORDER BY a,b) ... would request the sort order to be {a, b} because {a} is a subset of the sort order of {a,b}, but; SELECT agg(a ORDER BY a),agg2(a ORDER BY c) ... would just pick a plan ordered by {a} (we give precedence to aggregates which are earlier in the targetlist). SELECT agg(a ORDER BY a),agg2(a ORDER BY b),agg3(a ORDER BY b) ... would choose to order by {b} since two aggregates suit that vs just one that requires input ordered by {a}. Author: David Rowley Reviewed-by: Ronan Dunklau, James Coleman, Ranier Vilela, Richard Guo, Tom Lane Discussion: https://postgr.es/m/CAApHDvpHzfo92%3DR4W0%2BxVua3BUYCKMckWAmo-2t_KiXN-wYH%3Dw%40mail.gmail.com
2022-07-06Remove size increase in ExprEvalStep caused by hashed saopsDavid Rowley
50e17ad28 increased the size of ExprEvalStep from 64 bytes up to 88 bytes. Lots of effort was spent during the development of the current expression evaluation code to make an instance of this struct as small as possible. Making this struct larger than needed reduces CPU cache efficiency during expression evaluation which causes noticeable slowdowns during query execution. In order to reduce the size of the struct, here we remove the fn_addr field. The values from this field can be obtained via fcinfo, just with some extra pointer dereferencing. The extra indirection does not seem to cause any noticeable slowdowns. Various other fields have been moved into the ScalarArrayOpExprHashTable struct. These fields are only used when the ScalarArrayOpExprHashTable pointer has already been dereferenced, so no additional pointer dereferences occur for these. Here we also make hash_fcinfo_data the last field in ScalarArrayOpExprHashTable so that we can avoid a further pointer dereference to get the FunctionCallInfoBaseData. This also saves a call to palloc(). 50e17ad28 was added in 14, but it's too late to adjust the size of the ExprEvalStep in that version, so here we just backpatch to 15, which is currently in beta. Author: Andres Freund, David Rowley Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de Backpatch-through: 15
2022-07-05expression eval: Fix EEOP_JSON_CONSTRUCTOR and EEOP_JSONEXPR size.Andres Freund
The new expression step types increased the size of ExprEvalStep by ~4 for all types of expression steps, slowing down expression evaluation noticeably. Move them out of line. There's other issues with these expression steps, but addressing them is largely independent of this aspect. Author: Andres Freund <andres@anarazel.de> Reviewed-By: Andrew Dunstan <andrew@dunslane.net> Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de Backpatch: 15-
2022-05-12Pre-beta mechanical code beautification.Tom Lane
Run pgindent, pgperltidy, and reformat-dat-files. I manually fixed a couple of comments that pgindent uglified.
2022-04-04JSON_TABLEAndrew Dunstan
This feature allows jsonb data to be treated as a table and thus used in a FROM clause like other tabular data. Data can be selected from the jsonb using jsonpath expressions, and hoisted out of nested structures in the jsonb to form multiple rows, more or less like an outer join. Nikita Glukhov Reviewers have included (in no particular order) Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zhihong Yu (whose name I previously misspelled), Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby. Discussion: https://postgr.es/m/7e2cb85d-24cf-4abb-30a5-1a33715959bd@postgrespro.ru
2022-03-30SQL JSON functionsAndrew Dunstan
This Patch introduces three SQL standard JSON functions: JSON() (incorrectly mentioned in my commit message for f4fb45d15c) 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. Nikita Glukhov 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/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
2022-03-29SQL/JSON query functionsAndrew Dunstan
This introduces the SQL/JSON functions for querying JSON data using jsonpath expressions. The functions are: JSON_EXISTS() JSON_QUERY() JSON_VALUE() All of these functions only operate on jsonb. The workaround for now is to cast the argument to jsonb. JSON_EXISTS() tests if the jsonpath expression applied to the jsonb value yields any values. JSON_VALUE() must return a single value, and an error occurs if it tries to return multiple values. JSON_QUERY() must return a json object or array, and there are various WRAPPER options for handling scalar or multi-value results. Both these functions have options for handling EMPTY and ERROR conditions. Nikita Glukhov 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/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
2022-03-28IS JSON predicateAndrew Dunstan
This patch intrdocuces 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 an IS and IS NOT variant. The tests are: IS JSON [VALUE] IS JSON ARRAY IS JSON OBJECT IS JSON SCALAR IS JSON WITH | WITHOUT UNIQUE KEYS These are mostly self-explanatory, but note that IS JSON WITHOUT UNIQUE KEYS is true whenever IS JSON is true, and IS JSON WITH UNIQUE KEYS is true whenever IS JSON is true except it IS JSON OBJECT is true and there are duplicate keys (which is never the case when applied to jsonb values). Nikita Glukhov 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/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
2022-03-27SQL/JSON constructorsAndrew Dunstan
This patch introduces the SQL/JSON standard constructors for JSON: JSON() JSON_ARRAY() JSON_ARRAYAGG() JSON_OBJECT() JSON_OBJECTAGG() For the most part these functions provide facilities that mimic existing json/jsonb functions. However, they also offer some useful additional functionality. In addition to text input, the JSON() function accepts bytea input, which it will decode and constuct a json value from. The other functions provide useful options for handling duplicate keys and null values. This series of patches will be followed by a consolidated documentation patch. Nikita Glukhov 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/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
2022-03-27Common SQL/JSON clausesAndrew Dunstan
This introduces some of the building blocks used by the SQL/JSON constructor and query functions. Specifically, it provides node executor and grammar support for the FORMAT JSON [ENCODING foo] clause, and values decorated with it, and for the RETURNING clause. The following SQL/JSON patches will leverage these. Nikita Glukhov (who probably deserves an award for perseverance). 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/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
2022-03-22Revert "Common SQL/JSON clauses"Andrew Dunstan
This reverts commit 865fe4d5df560a6f5353da652018ff876978ad2d. This has caused issues with a significant number of buildfarm members
2022-03-22Common SQL/JSON clausesAndrew Dunstan
This introduces some of the building blocks used by the SQL/JSON constructor and query functions. Specifically, it provides node executor and grammar support for the FORMAT JSON [ENCODING foo] clause, and values decorated with it, and for the RETURNING clause. The following SQL/JSON patches will leverage these. Nikita Glukhov (who probably deserves an award for perseverance). Reviewers have included (in no particular order) Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup. Erik Rijkers, Zihong Yu and Himanshu Upadhyaya. Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
2022-03-17Revert applying column aliases to the output of whole-row Vars.Tom Lane
In commit bf7ca1587, I had the bright idea that we could make the result of a whole-row Var (that is, foo.*) track any column aliases that had been applied to the FROM entry the Var refers to. However, that's not terribly logically consistent, because now the output of the Var is no longer of the named composite type that the Var claims to emit. bf7ca1587 tried to handle that by changing the output tuple values to be labeled with a blessed RECORD type, but that's really pretty disastrous: we can wind up storing such tuples onto disk, whereupon they're not readable by other sessions. The only practical fix I can see is to give up on what bf7ca1587 tried to do, and say that the column names of tuples produced by a whole-row Var are always those of the underlying named composite type, query aliases or no. While this introduces some inconsistencies, it removes others, so it's not that awful in the abstract. What *is* kind of awful is to make such a behavioral change in a back-patched bug fix. But corrupt data is worse, so back-patched it will be. (A workaround available to anyone who's unhappy about this is to introduce an extra level of sub-SELECT, so that the whole-row Var is referring to the sub-SELECT's output and not to a named table type. Then the Var is of type RECORD to begin with and there's no issue.) Per report from Miles Delahunty. The faulty commit dates to 9.5, so back-patch to all supported branches. Discussion: https://postgr.es/m/2950001.1638729947@sss.pgh.pa.us
2022-01-07Update copyright for 2022Bruce Momjian
Backpatch-through: 10
2021-12-15Always use ReleaseTupleDesc after lookup_rowtype_tupdesc et al.Tom Lane
The API spec for lookup_rowtype_tupdesc previously said you could use either ReleaseTupleDesc or DecrTupleDescRefCount. However, the latter choice means the caller must be certain that the returned tupdesc is refcounted. I don't recall right now whether that was always true when this spec was written, but it's certainly not always true since we introduced shared record typcaches for parallel workers. That means that callers using DecrTupleDescRefCount are dependent on typcache behavior details that they probably shouldn't be. Hence, change the API spec to say that you must call ReleaseTupleDesc, and fix the half-dozen callers that weren't. AFAICT this is just future-proofing, there's no live bug here. So no back-patch. Per gripe from Chapman Flack. Discussion: https://postgr.es/m/61B901A4.1050808@anastigmatix.net