From 676887a3b0b8e3c0348ac3f82ab0d16e9a24bd43 Mon Sep 17 00:00:00 2001 From: Alexander Korotkov Date: Sun, 31 Jan 2021 23:50:40 +0300 Subject: Implementation of subscripting for jsonb Subscripting for jsonb does not support slices, does not have a limit for the number of subscripts, and an assignment expects a replace value to have jsonb type. There is also one functional difference between assignment via subscripting and assignment via jsonb_set(). When an original jsonb container is NULL, the subscripting replaces it with an empty jsonb and proceeds with an assignment. For the sake of code reuse, we rearrange some parts of jsonb functionality to allow the usage of the same functions for jsonb_set and assign subscripting operation. The original idea belongs to Oleg Bartunov. Catversion is bumped. Discussion: https://postgr.es/m/CA%2Bq6zcV8qvGcDXurwwgUbwACV86Th7G80pnubg42e-p9gsSf%3Dg%40mail.gmail.com Discussion: https://postgr.es/m/CA%2Bq6zcX3mdxGCgdThzuySwH-ApyHHM-G4oB1R0fn0j2hZqqkLQ%40mail.gmail.com Discussion: https://postgr.es/m/CA%2Bq6zcVDuGBv%3DM0FqBYX8DPebS3F_0KQ6OVFobGJPM507_SZ_w%40mail.gmail.com Discussion: https://postgr.es/m/CA%2Bq6zcVovR%2BXY4mfk-7oNk-rF91gH0PebnNfuUjuuDsyHjOcVA%40mail.gmail.com Author: Dmitry Dolgov Reviewed-by: Tom Lane, Arthur Zakirov, Pavel Stehule, Dian M Fay Reviewed-by: Andrew Dunstan, Chapman Flack, Merlin Moncure, Peter Geoghegan Reviewed-by: Alvaro Herrera, Jim Nasby, Josh Berkus, Victor Wagner Reviewed-by: Aleksander Alekseev, Robert Haas, Oleg Bartunov --- src/backend/utils/adt/jsonb_util.c | 72 ++++++++++++++++++++++++++++++++------ 1 file changed, 62 insertions(+), 10 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 0ce66411ae1..57111877959 100644 --- a/src/backend/utils/adt/jsonb_util.c +++ b/src/backend/utils/adt/jsonb_util.c @@ -68,18 +68,25 @@ static JsonbValue *pushJsonbValueScalar(JsonbParseState **pstate, JsonbIteratorToken seq, JsonbValue *scalarVal); +void +JsonbToJsonbValue(Jsonb *jsonb, JsonbValue *val) +{ + val->type = jbvBinary; + val->val.binary.data = &jsonb->root; + val->val.binary.len = VARSIZE(jsonb) - VARHDRSZ; +} + /* * Turn an in-memory JsonbValue into a Jsonb for on-disk storage. * - * There isn't a JsonbToJsonbValue(), because generally we find it more - * convenient to directly iterate through the Jsonb representation and only - * really convert nested scalar values. JsonbIteratorNext() does this, so that - * clients of the iteration code don't have to directly deal with the binary - * representation (JsonbDeepContains() is a notable exception, although all - * exceptions are internal to this module). In general, functions that accept - * a JsonbValue argument are concerned with the manipulation of scalar values, - * or simple containers of scalar values, where it would be inconvenient to - * deal with a great amount of other state. + * Generally we find it more convenient to directly iterate through the Jsonb + * representation and only really convert nested scalar values. + * JsonbIteratorNext() does this, so that clients of the iteration code don't + * have to directly deal with the binary representation (JsonbDeepContains() is + * a notable exception, although all exceptions are internal to this module). + * In general, functions that accept a JsonbValue argument are concerned with + * the manipulation of scalar values, or simple containers of scalar values, + * where it would be inconvenient to deal with a great amount of other state. */ Jsonb * JsonbValueToJsonb(JsonbValue *val) @@ -563,6 +570,30 @@ pushJsonbValue(JsonbParseState **pstate, JsonbIteratorToken seq, JsonbValue *res = NULL; JsonbValue v; JsonbIteratorToken tok; + int i; + + if (jbval && (seq == WJB_ELEM || seq == WJB_VALUE) && jbval->type == jbvObject) + { + pushJsonbValue(pstate, WJB_BEGIN_OBJECT, NULL); + for (i = 0; i < jbval->val.object.nPairs; i++) + { + pushJsonbValue(pstate, WJB_KEY, &jbval->val.object.pairs[i].key); + pushJsonbValue(pstate, WJB_VALUE, &jbval->val.object.pairs[i].value); + } + + return pushJsonbValue(pstate, WJB_END_OBJECT, NULL); + } + + if (jbval && (seq == WJB_ELEM || seq == WJB_VALUE) && jbval->type == jbvArray) + { + pushJsonbValue(pstate, WJB_BEGIN_ARRAY, NULL); + for (i = 0; i < jbval->val.array.nElems; i++) + { + pushJsonbValue(pstate, WJB_ELEM, &jbval->val.array.elems[i]); + } + + return pushJsonbValue(pstate, WJB_END_ARRAY, NULL); + } if (!jbval || (seq != WJB_ELEM && seq != WJB_VALUE) || jbval->type != jbvBinary) @@ -573,9 +604,30 @@ pushJsonbValue(JsonbParseState **pstate, JsonbIteratorToken seq, /* unpack the binary and add each piece to the pstate */ it = JsonbIteratorInit(jbval->val.binary.data); + + if ((jbval->val.binary.data->header & JB_FSCALAR) && *pstate) + { + tok = JsonbIteratorNext(&it, &v, true); + Assert(tok == WJB_BEGIN_ARRAY); + Assert(v.type == jbvArray && v.val.array.rawScalar); + + tok = JsonbIteratorNext(&it, &v, true); + Assert(tok == WJB_ELEM); + + res = pushJsonbValueScalar(pstate, seq, &v); + + tok = JsonbIteratorNext(&it, &v, true); + Assert(tok == WJB_END_ARRAY); + Assert(it == NULL); + + return res; + } + while ((tok = JsonbIteratorNext(&it, &v, false)) != WJB_DONE) res = pushJsonbValueScalar(pstate, tok, - tok < WJB_BEGIN_ARRAY ? &v : NULL); + tok < WJB_BEGIN_ARRAY || + (tok == WJB_BEGIN_ARRAY && + v.val.array.rawScalar) ? &v : NULL); return res; } -- cgit v1.2.3