From df73c141596e10581ec4b9816d5ca71955591fef Mon Sep 17 00:00:00 2001 From: Alexander Korotkov Date: Thu, 9 Jul 2026 21:35:56 +0300 Subject: [PATCH v2 1/4] Revert cascading of JSON_TABLE's ON ERROR 86ab7f4c721d commit made the table-level ON ERROR clause serve as the default ON ERROR for columns lacking their own, so that a top-level ERROR ON ERROR turned per-column evaluation errors into hard errors. The SQL standard does mandate this cascade, but introducing it should be a deliberate, separately-documented change, so restore the previous behavior for now. This also reverts the paired ruleutils.c logic that deparsed a column's behavior against an ERROR default: that dropped an explicit ERROR ON EMPTY from a dumped view, and otherwise emitted a redundant NULL ON EMPTY. Reported-by: Thom Brown Discussion: https://postgr.es/m/CAA-aLv7aZGSExnbjJRw8eKkoXbu34TdoKLLA2gPye3aHjO5OSA@mail.gmail.com --- src/backend/parser/parse_jsontable.c | 13 +++---------- src/backend/utils/adt/ruleutils.c | 4 ---- src/test/regress/expected/sqljson_jsontable.out | 11 ++++++++++- src/test/regress/sql/sqljson_jsontable.sql | 5 +++++ 4 files changed, 18 insertions(+), 15 deletions(-) diff --git a/src/backend/parser/parse_jsontable.c b/src/backend/parser/parse_jsontable.c index ef042830f02..674ab37c45a 100644 --- a/src/backend/parser/parse_jsontable.c +++ b/src/backend/parser/parse_jsontable.c @@ -49,8 +49,7 @@ static JsonTablePlan *transformJsonTableNestedColumns(JsonTableParseContext *cxt List *columns); static JsonFuncExpr *transformJsonTableColumn(JsonTableColumn *jtc, Node *contextItemExpr, - List *passingArgs, - bool errorOnError); + List *passingArgs); static bool isCompositeType(Oid typid); static JsonTablePlan *makeJsonTablePathScan(JsonTableParseContext *cxt, JsonTablePathSpec *pathspec, @@ -363,12 +362,8 @@ appendJsonTableColumns(JsonTableParseContext *cxt, List *columns, List *passingA { ListCell *col; ParseState *pstate = cxt->pstate; - JsonTable *jt = cxt->jt; TableFunc *tf = cxt->tf; bool ordinality_found = false; - JsonBehavior *on_error = jt->on_error; - bool errorOnError = on_error && - on_error->btype == JSON_BEHAVIOR_ERROR; Oid contextItemTypid = exprType(tf->docexpr); foreach(col, columns) @@ -427,7 +422,7 @@ appendJsonTableColumns(JsonTableParseContext *cxt, List *columns, List *passingA param->typeMod = -1; jfe = transformJsonTableColumn(rawc, (Node *) param, - passingArgs, errorOnError); + passingArgs); colexpr = transformExpr(pstate, (Node *) jfe, EXPR_KIND_FROM_FUNCTION); @@ -482,7 +477,7 @@ isCompositeType(Oid typid) */ static JsonFuncExpr * transformJsonTableColumn(JsonTableColumn *jtc, Node *contextItemExpr, - List *passingArgs, bool errorOnError) + List *passingArgs) { Node *pathspec; JsonFuncExpr *jfexpr = makeNode(JsonFuncExpr); @@ -524,8 +519,6 @@ transformJsonTableColumn(JsonTableColumn *jtc, Node *contextItemExpr, jfexpr->output->returning->format = jtc->format; jfexpr->on_empty = jtc->on_empty; jfexpr->on_error = jtc->on_error; - if (jfexpr->on_error == NULL && errorOnError) - jfexpr->on_error = makeJsonBehavior(JSON_BEHAVIOR_ERROR, NULL, -1); jfexpr->quotes = jtc->quotes; jfexpr->wrapper = jtc->wrapper; jfexpr->location = jtc->location; diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c index b3aef797e7d..b83c8b9d7b5 100644 --- a/src/backend/utils/adt/ruleutils.c +++ b/src/backend/utils/adt/ruleutils.c @@ -12799,7 +12799,6 @@ get_json_table_columns(TableFunc *tf, JsonTablePathScan *scan, bool showimplicit) { StringInfo buf = context->buf; - JsonExpr *jexpr = castNode(JsonExpr, tf->docexpr); ListCell *lc_colname; ListCell *lc_coltype; ListCell *lc_coltypmod; @@ -12879,9 +12878,6 @@ get_json_table_columns(TableFunc *tf, JsonTablePathScan *scan, default_behavior = JSON_BEHAVIOR_NULL; } - if (jexpr->on_error->btype == JSON_BEHAVIOR_ERROR) - default_behavior = JSON_BEHAVIOR_ERROR; - appendStringInfoString(buf, " PATH "); get_json_path_spec(colexpr->path_spec, context, showimplicit); diff --git a/src/test/regress/expected/sqljson_jsontable.out b/src/test/regress/expected/sqljson_jsontable.out index 1530ef8afe0..e714e36baba 100644 --- a/src/test/regress/expected/sqljson_jsontable.out +++ b/src/test/regress/expected/sqljson_jsontable.out @@ -547,6 +547,15 @@ SELECT * FROM JSON_TABLE(jsonb '1', '$' COLUMNS (a int PATH 'strict $.a' ERROR O ERROR: jsonpath member accessor can only be applied to an object SELECT * FROM JSON_TABLE(jsonb '1', '$' COLUMNS (a int PATH 'lax $.a' ERROR ON EMPTY) ERROR ON ERROR) jt; ERROR: no SQL/JSON item found for specified path of column "a" +-- Table-level ERROR ON ERROR is not propagated to a column lacking its own +-- ON ERROR clause: the column keeps the default NULL ON ERROR behavior, so a +-- conversion failure yields NULL rather than raising an error. +SELECT * FROM JSON_TABLE(jsonb '"err"', '$' COLUMNS (a int PATH '$') ERROR ON ERROR) jt; + a +--- + +(1 row) + SELECT * FROM JSON_TABLE(jsonb '"a"', '$' COLUMNS (a int PATH '$' DEFAULT 1 ON EMPTY DEFAULT 2 ON ERROR)) jt; a --- @@ -1821,7 +1830,7 @@ CREATE OR REPLACE VIEW public.json_table_view9 AS FROM JSON_TABLE( '"a"'::text, '$' AS json_table_path_0 COLUMNS ( - a text PATH '$' NULL ON EMPTY + a text PATH '$' ) ERROR ON ERROR ) DROP VIEW json_table_view8, json_table_view9; diff --git a/src/test/regress/sql/sqljson_jsontable.sql b/src/test/regress/sql/sqljson_jsontable.sql index d71d57e99b2..22f9c5ae92f 100644 --- a/src/test/regress/sql/sqljson_jsontable.sql +++ b/src/test/regress/sql/sqljson_jsontable.sql @@ -266,6 +266,11 @@ SELECT * FROM JSON_TABLE(jsonb '1', '$' COLUMNS (a int PATH '$.a' ERROR ON EMPTY SELECT * FROM JSON_TABLE(jsonb '1', '$' COLUMNS (a int PATH 'strict $.a' ERROR ON ERROR) ERROR ON ERROR) jt; SELECT * FROM JSON_TABLE(jsonb '1', '$' COLUMNS (a int PATH 'lax $.a' ERROR ON EMPTY) ERROR ON ERROR) jt; +-- Table-level ERROR ON ERROR is not propagated to a column lacking its own +-- ON ERROR clause: the column keeps the default NULL ON ERROR behavior, so a +-- conversion failure yields NULL rather than raising an error. +SELECT * FROM JSON_TABLE(jsonb '"err"', '$' COLUMNS (a int PATH '$') ERROR ON ERROR) jt; + SELECT * FROM JSON_TABLE(jsonb '"a"', '$' COLUMNS (a int PATH '$' DEFAULT 1 ON EMPTY DEFAULT 2 ON ERROR)) jt; SELECT * FROM JSON_TABLE(jsonb '"a"', '$' COLUMNS (a int PATH 'strict $.a' DEFAULT 1 ON EMPTY DEFAULT 2 ON ERROR)) jt; SELECT * FROM JSON_TABLE(jsonb '"a"', '$' COLUMNS (a int PATH 'lax $.a' DEFAULT 1 ON EMPTY DEFAULT 2 ON ERROR)) jt; -- 2.50.1 (Apple Git-155)