From dbe9b3e1614721842d488ef7a8a93f91ac417439 Mon Sep 17 00:00:00 2001 From: jian he Date: Wed, 16 Sep 2026 10:08:15 +0800 Subject: [PATCH v1 1/1] fix SQL/JSON DEFAULT expression error rethrow If the DEFAULT expression in ON ERROR or ON EMPTY clause is compiled unconditionally in an error-safe manner, and the point of that is to rethrow the errors later, then we need an unconditional step to check whether the preceding expression reported one. Discusssion: https://postgr.es/m/ --- src/backend/executor/execExpr.c | 31 ++++++------------- src/backend/executor/execExprInterp.c | 7 +++++ .../regress/expected/sqljson_jsontable.out | 13 ++++++++ .../regress/expected/sqljson_queryfuncs.out | 16 ++++++++++ src/test/regress/sql/sqljson_jsontable.sql | 5 +++ src/test/regress/sql/sqljson_queryfuncs.sql | 7 +++++ 6 files changed, 58 insertions(+), 21 deletions(-) diff --git a/src/backend/executor/execExpr.c b/src/backend/executor/execExpr.c index 82e846a1f4f..a9882bbb3c4 100644 --- a/src/backend/executor/execExpr.c +++ b/src/backend/executor/execExpr.c @@ -4951,16 +4951,11 @@ ExecInitJsonExpr(JsonExpr *jsexpr, ExprState *state, * Add a COERCION_FINISH step to check for errors that may occur when * coercing and rethrow them. */ - if (jsexpr->on_error->coerce || - IsA(jsexpr->on_error->expr, CoerceViaIO) || - IsA(jsexpr->on_error->expr, CoerceToDomain)) - { - scratch->opcode = EEOP_JSONEXPR_COERCION_FINISH; - scratch->resvalue = resv; - scratch->resnull = resnull; - scratch->d.jsonexpr.jsestate = jsestate; - ExprEvalPushStep(state, scratch); - } + scratch->opcode = EEOP_JSONEXPR_COERCION_FINISH; + scratch->resvalue = resv; + scratch->resnull = resnull; + scratch->d.jsonexpr.jsestate = jsestate; + ExprEvalPushStep(state, scratch); /* JUMP to end to skip the ON EMPTY steps added below. */ jumps_to_end = lappend_int(jumps_to_end, state->steps_len); @@ -5014,17 +5009,11 @@ ExecInitJsonExpr(JsonExpr *jsexpr, ExprState *state, * Add a COERCION_FINISH step to check for errors that may occur when * coercing and rethrow them. */ - if (jsexpr->on_empty->coerce || - IsA(jsexpr->on_empty->expr, CoerceViaIO) || - IsA(jsexpr->on_empty->expr, CoerceToDomain)) - { - - scratch->opcode = EEOP_JSONEXPR_COERCION_FINISH; - scratch->resvalue = resv; - scratch->resnull = resnull; - scratch->d.jsonexpr.jsestate = jsestate; - ExprEvalPushStep(state, scratch); - } + scratch->opcode = EEOP_JSONEXPR_COERCION_FINISH; + scratch->resvalue = resv; + scratch->resnull = resnull; + scratch->d.jsonexpr.jsestate = jsestate; + ExprEvalPushStep(state, scratch); } foreach(lc, jumps_to_end) diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c index 397219f7a3a..91d1043ecf6 100644 --- a/src/backend/executor/execExprInterp.c +++ b/src/backend/executor/execExprInterp.c @@ -5188,6 +5188,13 @@ ExecEvalJsonCoercion(ExprState *state, ExprEvalStep *op, { ErrorSaveContext *escontext = op->d.jsonexpr_coercion.escontext; + if (SOFT_ERROR_OCCURRED(escontext)) + { + *op->resnull = true; + *op->resvalue = (Datum) 0; + return; + } + /* * Prepare to call json_populate_type() to coerce the boolean result of * JSON_EXISTS_OP to the target type. If the target type is integer or a diff --git a/src/test/regress/expected/sqljson_jsontable.out b/src/test/regress/expected/sqljson_jsontable.out index ae64dbed303..d6a22ba8205 100644 --- a/src/test/regress/expected/sqljson_jsontable.out +++ b/src/test/regress/expected/sqljson_jsontable.out @@ -672,6 +672,19 @@ SELECT a, a::bool FROM JSON_TABLE(jsonb '{"a":1}', '$' COLUMNS (a dint4_0 EXISTS 1 | t (1 row) +-- soft errors in the ON EMPTY expression must be rethrown +SELECT * FROM JSON_TABLE('{}', '$' COLUMNS (a int PATH '$.a' DEFAULT (0::dint4_0 + 0) ON EMPTY)); +ERROR: could not coerce ON EMPTY expression (DEFAULT) to the RETURNING type +DETAIL: value for domain dint4_0 violates check constraint "dint4_0_check" +SELECT * FROM JSON_TABLE('{}', '$' COLUMNS (a int PATH '$.a' KEEP QUOTES DEFAULT (0::dint4_0 + 0) ON EMPTY)); +ERROR: could not coerce ON EMPTY expression (DEFAULT) to the RETURNING type +DETAIL: value for domain dint4_0 violates check constraint "dint4_0_check" +SELECT * FROM JSON_TABLE('{}', '$' COLUMNS (a int PATH '$.a' DEFAULT (('a' || (random() * 0)::int)::int + 0) ON EMPTY)); +ERROR: could not coerce ON EMPTY expression (DEFAULT) to the RETURNING type +DETAIL: invalid input syntax for type integer: "a0" +SELECT * FROM JSON_TABLE('{}', '$' COLUMNS (a int PATH '$.a' KEEP QUOTES DEFAULT (('a' || (random() * 0)::int)::int + 0) ON EMPTY)); +ERROR: could not coerce ON EMPTY expression (DEFAULT) to the RETURNING type +DETAIL: invalid input syntax for type integer: "a0" DROP DOMAIN dint4, dint4_0; -- JSON_TABLE: WRAPPER/QUOTES clauses on scalar columns SELECT * FROM JSON_TABLE(jsonb '"world"', '$' COLUMNS (item text PATH '$' KEEP QUOTES ON SCALAR STRING)); diff --git a/src/test/regress/expected/sqljson_queryfuncs.out b/src/test/regress/expected/sqljson_queryfuncs.out index ff64dce0c59..0c3672b67a2 100644 --- a/src/test/regress/expected/sqljson_queryfuncs.out +++ b/src/test/regress/expected/sqljson_queryfuncs.out @@ -1489,6 +1489,22 @@ ERROR: invalid ON ERROR behavior LINE 1: SELECT JSON_QUERY(jsonb '1', '$' TRUE ON ERROR); ^ DETAIL: Only ERROR, NULL, EMPTY ARRAY, EMPTY OBJECT, or DEFAULT expression is allowed in ON ERROR for JSON_QUERY(). +-- DEFAULT expression ON ERROR / EMPTY soft error should rethrow unconditionally +SELECT JSON_VALUE('"a"', '$' RETURNING sqljsonb_int_not_null DEFAULT NULL ON ERROR); +ERROR: could not coerce ON ERROR expression (DEFAULT) to the RETURNING type +DETAIL: domain sqljsonb_int_not_null does not allow null values +SELECT JSON_VALUE('"a"', '$' RETURNING int DEFAULT (NULL::sqljsonb_int_not_null + 0) ON ERROR); +ERROR: could not coerce ON ERROR expression (DEFAULT) to the RETURNING type +DETAIL: domain sqljsonb_int_not_null does not allow null values +SELECT JSON_QUERY('"a"', '$' RETURNING int DEFAULT (NULL::sqljsonb_int_not_null + 0) ON ERROR); +ERROR: could not coerce ON ERROR expression (DEFAULT) to the RETURNING type +DETAIL: domain sqljsonb_int_not_null does not allow null values +SELECT JSON_VALUE('"a"', '$' RETURNING int DEFAULT (('a' || (random() * 0)::int)::int + 0) ON ERROR); +ERROR: could not coerce ON ERROR expression (DEFAULT) to the RETURNING type +DETAIL: invalid input syntax for type integer: "a0" +SELECT JSON_QUERY('"a"', '$' RETURNING int DEFAULT (('a' || (random() * 0)::int)::int + 0) ON ERROR); +ERROR: could not coerce ON ERROR expression (DEFAULT) to the RETURNING type +DETAIL: invalid input syntax for type integer: "a0" -- Test implicit coercion to a domain over fixed-length type specified in -- RETURNING CREATE DOMAIN queryfuncs_char2 AS char(2); diff --git a/src/test/regress/sql/sqljson_jsontable.sql b/src/test/regress/sql/sqljson_jsontable.sql index 2a33aaec57f..7f0b54b1121 100644 --- a/src/test/regress/sql/sqljson_jsontable.sql +++ b/src/test/regress/sql/sqljson_jsontable.sql @@ -311,6 +311,11 @@ SELECT a, a::bool FROM JSON_TABLE(jsonb '{"a":1}', '$' COLUMNS (a dint4_0 EXISTS SELECT a, a::bool FROM JSON_TABLE(jsonb '{"a":1}', '$' COLUMNS (a dint4_0 EXISTS PATH '$.b' ERROR ON ERROR)); SELECT a, a::bool FROM JSON_TABLE(jsonb '{"a":1}', '$' COLUMNS (a dint4_0 EXISTS PATH '$.b' FALSE ON ERROR)); SELECT a, a::bool FROM JSON_TABLE(jsonb '{"a":1}', '$' COLUMNS (a dint4_0 EXISTS PATH '$.b' TRUE ON ERROR)); +-- soft errors in the ON EMPTY expression must be rethrown +SELECT * FROM JSON_TABLE('{}', '$' COLUMNS (a int PATH '$.a' DEFAULT (0::dint4_0 + 0) ON EMPTY)); +SELECT * FROM JSON_TABLE('{}', '$' COLUMNS (a int PATH '$.a' KEEP QUOTES DEFAULT (0::dint4_0 + 0) ON EMPTY)); +SELECT * FROM JSON_TABLE('{}', '$' COLUMNS (a int PATH '$.a' DEFAULT (('a' || (random() * 0)::int)::int + 0) ON EMPTY)); +SELECT * FROM JSON_TABLE('{}', '$' COLUMNS (a int PATH '$.a' KEEP QUOTES DEFAULT (('a' || (random() * 0)::int)::int + 0) ON EMPTY)); DROP DOMAIN dint4, dint4_0; -- JSON_TABLE: WRAPPER/QUOTES clauses on scalar columns diff --git a/src/test/regress/sql/sqljson_queryfuncs.sql b/src/test/regress/sql/sqljson_queryfuncs.sql index a69ef253f66..2f7e4b031be 100644 --- a/src/test/regress/sql/sqljson_queryfuncs.sql +++ b/src/test/regress/sql/sqljson_queryfuncs.sql @@ -493,6 +493,13 @@ SELECT JSON_EXISTS(jsonb '1', '$' DEFAULT 1 ON ERROR); SELECT JSON_VALUE(jsonb '1', '$' EMPTY ON ERROR); SELECT JSON_QUERY(jsonb '1', '$' TRUE ON ERROR); +-- DEFAULT expression ON ERROR / EMPTY soft error should rethrow unconditionally +SELECT JSON_VALUE('"a"', '$' RETURNING sqljsonb_int_not_null DEFAULT NULL ON ERROR); +SELECT JSON_VALUE('"a"', '$' RETURNING int DEFAULT (NULL::sqljsonb_int_not_null + 0) ON ERROR); +SELECT JSON_QUERY('"a"', '$' RETURNING int DEFAULT (NULL::sqljsonb_int_not_null + 0) ON ERROR); +SELECT JSON_VALUE('"a"', '$' RETURNING int DEFAULT (('a' || (random() * 0)::int)::int + 0) ON ERROR); +SELECT JSON_QUERY('"a"', '$' RETURNING int DEFAULT (('a' || (random() * 0)::int)::int + 0) ON ERROR); + -- Test implicit coercion to a domain over fixed-length type specified in -- RETURNING CREATE DOMAIN queryfuncs_char2 AS char(2); -- 2.34.1