From 4c24c0f89c91172fbf4becb9a0be89c26fc21135 Mon Sep 17 00:00:00 2001 From: Dmitrii Dolgov <9erthalion6@gmail.com> Date: Thu, 7 Jan 2021 09:04:39 +0100 Subject: [PATCH v45 3/3] Replace assuming a composite object on a scalar For jsonb subscripting assignment it could happen that the provided path assumes an object or an array at some level, but the source jsonb has a scalar value there. Originally the update operation will be skipped and no message will be shown that nothing happened. Return an error to indicate such situations. --- doc/src/sgml/json.sgml | 22 ++++++++++++++++++++-- src/backend/utils/adt/jsonfuncs.c | 11 +++++++++++ src/test/regress/expected/jsonb.out | 12 ++++++++++++ src/test/regress/sql/jsonb.sql | 8 ++++++++ 4 files changed, 51 insertions(+), 2 deletions(-) diff --git a/doc/src/sgml/json.sgml b/doc/src/sgml/json.sgml index 9af015d222..924762e128 100644 --- a/doc/src/sgml/json.sgml +++ b/doc/src/sgml/json.sgml @@ -612,8 +612,23 @@ SELECT jdoc->'guid', jdoc->'name' FROM api WHERE jdoc @> '{"tags": ["qu path argument in jsonb_set function, e.g. in case of arrays it is a 0-based operation or that negative integers that appear in path count from the end of JSON arrays. - The result of subscripting expressions is always jsonb data type. An - example of subscripting syntax: + The result of subscripting expressions is always jsonb data type. + + + UPDATE statements may use subscripting in the + SET clause to modify jsonb values. Every + affected value must conform to the path defined by the subscript(s). If the + path contradicts structure of modified jsonb for any individual + value (e.g. path val['a']['b']['c'] assumes keys + 'a' and 'b' have object values + assigned to them, but if val['a'] or + val['b'] is null, a string, or a number, then the path + contradicts with the existing structure), an error is raised even if other + values do conform. + + + + An example of subscripting syntax: -- Extract value by key SELECT ('{"a": 1}'::jsonb)['a']; @@ -628,6 +643,9 @@ SELECT ('[1, "2", null]'::jsonb)[1]; -- needs to be of jsonb type as well UPDATE table_name SET jsonb_field['key'] = '1'; +-- This will raise an error if jsonb_field is {"a": 1} +UPDATE table_name SET jsonb_field['a']['b']['c'] = '1'; + -- Select records using where clause with subscripting. Since the result of -- subscripting is jsonb and we basically want to compare two jsonb objects, we -- need to put the value in double quotes to be able to convert it to jsonb. diff --git a/src/backend/utils/adt/jsonfuncs.c b/src/backend/utils/adt/jsonfuncs.c index f14f6c3191..ebc0b06f5b 100644 --- a/src/backend/utils/adt/jsonfuncs.c +++ b/src/backend/utils/adt/jsonfuncs.c @@ -4943,6 +4943,17 @@ setPath(JsonbIterator **it, Datum *path_elems, break; case WJB_ELEM: case WJB_VALUE: + /* + * If instructed complain about attempts to replace whithin a + * scalar value. + */ + if ((op_type & JB_PATH_FILL_GAPS) && (level < path_len - 1)) + ereport(ERROR, + (errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("cannot replace existing key"), + errdetail("The path assumes key is a composite object, " + "but it is a scalar value."))); + res = pushJsonbValue(st, r, &v); break; default: diff --git a/src/test/regress/expected/jsonb.out b/src/test/regress/expected/jsonb.out index b7c268b53f..0df808c36d 100644 --- a/src/test/regress/expected/jsonb.out +++ b/src/test/regress/expected/jsonb.out @@ -5134,6 +5134,18 @@ select * from test_jsonb_subscript; 1 | {"a": [null, {"c": [null, null, 1]}]} (1 row) +-- trying replace assuming a composite object, but it's a scalar +delete from test_jsonb_subscript; +insert into test_jsonb_subscript values (1, '{"a": 1}'); +update test_jsonb_subscript set test_json['a']['b']['c'] = '1'; +ERROR: cannot replace existing key +DETAIL: The path assumes key is a composite object, but it is a scalar value. +update test_jsonb_subscript set test_json['a'][0]['c'] = '1'; +ERROR: cannot replace existing key +DETAIL: The path assumes key is a composite object, but it is a scalar value. +update test_jsonb_subscript set test_json['a'][0][0] = '1'; +ERROR: cannot replace existing key +DETAIL: The path assumes key is a composite object, but it is a scalar value. -- jsonb to tsvector select to_tsvector('{"a": "aaa bbb ddd ccc", "b": ["eee fff ggg"], "c": {"d": "hhh iii"}}'::jsonb); to_tsvector diff --git a/src/test/regress/sql/jsonb.sql b/src/test/regress/sql/jsonb.sql index 0320db0ea4..c62a2f9aec 100644 --- a/src/test/regress/sql/jsonb.sql +++ b/src/test/regress/sql/jsonb.sql @@ -1371,6 +1371,14 @@ insert into test_jsonb_subscript values (1, '{"a": []}'); update test_jsonb_subscript set test_json['a'][1]['c'][2] = '1'; select * from test_jsonb_subscript; +-- trying replace assuming a composite object, but it's a scalar + +delete from test_jsonb_subscript; +insert into test_jsonb_subscript values (1, '{"a": 1}'); +update test_jsonb_subscript set test_json['a']['b']['c'] = '1'; +update test_jsonb_subscript set test_json['a'][0]['c'] = '1'; +update test_jsonb_subscript set test_json['a'][0][0] = '1'; + -- jsonb to tsvector select to_tsvector('{"a": "aaa bbb ddd ccc", "b": ["eee fff ggg"], "c": {"d": "hhh iii"}}'::jsonb); -- 2.21.0