From f4fb45d15c59d7add2e1b81a9d477d0119a9691a Mon Sep 17 00:00:00 2001 From: Andrew Dunstan Date: Thu, 3 Mar 2022 13:02:10 -0500 Subject: SQL/JSON constructors 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 --- src/backend/utils/adt/jsonb_util.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) (limited to 'src/backend/utils/adt/jsonb_util.c') diff --git a/src/backend/utils/adt/jsonb_util.c b/src/backend/utils/adt/jsonb_util.c index 60442758b32..aa151a53d61 100644 --- a/src/backend/utils/adt/jsonb_util.c +++ b/src/backend/utils/adt/jsonb_util.c @@ -64,7 +64,8 @@ static int lengthCompareJsonbStringValue(const void *a, const void *b); static int lengthCompareJsonbString(const char *val1, int len1, const char *val2, int len2); static int lengthCompareJsonbPair(const void *a, const void *b, void *arg); -static void uniqueifyJsonbObject(JsonbValue *object); +static void uniqueifyJsonbObject(JsonbValue *object, bool unique_keys, + bool skip_nulls); static JsonbValue *pushJsonbValueScalar(JsonbParseState **pstate, JsonbIteratorToken seq, JsonbValue *scalarVal); @@ -689,7 +690,9 @@ pushJsonbValueScalar(JsonbParseState **pstate, JsonbIteratorToken seq, appendElement(*pstate, scalarVal); break; case WJB_END_OBJECT: - uniqueifyJsonbObject(&(*pstate)->contVal); + uniqueifyJsonbObject(&(*pstate)->contVal, + (*pstate)->unique_keys, + (*pstate)->skip_nulls); /* fall through! */ case WJB_END_ARRAY: /* Steps here common to WJB_END_OBJECT case */ @@ -732,6 +735,9 @@ pushState(JsonbParseState **pstate) JsonbParseState *ns = palloc(sizeof(JsonbParseState)); ns->next = *pstate; + ns->unique_keys = false; + ns->skip_nulls = false; + return ns; } @@ -1936,7 +1942,7 @@ lengthCompareJsonbPair(const void *a, const void *b, void *binequal) * Sort and unique-ify pairs in JsonbValue object */ static void -uniqueifyJsonbObject(JsonbValue *object) +uniqueifyJsonbObject(JsonbValue *object, bool unique_keys, bool skip_nulls) { bool hasNonUniq = false; @@ -1946,15 +1952,21 @@ uniqueifyJsonbObject(JsonbValue *object) qsort_arg(object->val.object.pairs, object->val.object.nPairs, sizeof(JsonbPair), lengthCompareJsonbPair, &hasNonUniq); - if (hasNonUniq) + if (hasNonUniq && unique_keys) + ereport(ERROR, + (errcode(ERRCODE_DUPLICATE_JSON_OBJECT_KEY_VALUE), + errmsg("duplicate JSON object key value"))); + + if (hasNonUniq || skip_nulls) { JsonbPair *ptr = object->val.object.pairs + 1, *res = object->val.object.pairs; while (ptr - object->val.object.pairs < object->val.object.nPairs) { - /* Avoid copying over duplicate */ - if (lengthCompareJsonbStringValue(ptr, res) != 0) + /* Avoid copying over duplicate or null */ + if (lengthCompareJsonbStringValue(ptr, res) != 0 && + (!skip_nulls || ptr->value.type != jbvNull)) { res++; if (ptr != res) -- cgit v1.2.3