On Tue, Jan 17, 2017 at 8:25 AM, Michael Paquier <michael.paqu...@gmail.com>
wrote:
> On Sun, Dec 18, 2016 at 1:27 AM, Dmitry Dolgov <9erthali...@gmail.com>
> wrote:
> > Speaking about implementation of `jsonb_delete_array` - it's fine, but I
> > would like to suggest two modifications:
> >
> > * create a separate helper function for jsonb delete operation, to use
> it in
> > both `jsonb_delete` and `jsonb_delete_array`. It will help to concentrate
> > related logic in one place.
>
> I am not sure that it is much a win as the code loses readability for
> a minimal refactoring. What would have been nice is to group as well
> jsonb_delete_idx but handling of the element deletion is really
> different there.
>
I agree with that. I agree with investigating it as an option, but I think
the lost readability is worse.
>
> > * use variadic arguments for `jsonb_delete_array`. For rare cases, when
> > someone decides to use this function directly instead of corresponding
> > operator. It will be more consistent with `jsonb_delete` from my point of
> > view, because it's transition from `jsonb_delete(data, 'key')` to
> > `jsonb_delete(data, 'key1', 'key2')` is more smooth, than to
> > `jsonb_delete(data, '{key1, key2}')`.
>
> That's a good idea.
>
I can see the point of that. In the particular usecase I built it for
originally though, the list of keys came from the application, in which
case binding them as an array was a lot more efficient (so as not to
require a whole lot of different prepared statements, one for each number
of parameters). But that should be workaround-able using the VARIADIC
keyword in the caller. Or by just using the operator.
> > I've attached a patch with these modifications. What do you think?
>
> Looking at both patches proposed, documentation is still missing in
> the list of jsonb operators as '-' is missing for arrays. I am marking
> this patch as waiting on author for now.
>
Added in updated patch. Do you see that as enough, or do we need it in some
more places in the docs as well?
--
Magnus Hagander
Me: http://www.hagander.net/
Work: http://www.redpill-linpro.com/
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 10e3186..af3d2aa 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -10845,6 +10845,14 @@ table2-mapping
</row>
<row>
<entry><literal>-</literal></entry>
+ <entry><type>text[]</type></entry>
+ <entry>Delete multiple key/value pairs or <emphasis>string</emphasis>
+ elements from left operand. Key/value pairs are matched based
+ on their key value.</entry>
+ <entry><literal>'{"a": "b", "c": "d"}'::jsonb - '{a,c}'::text[] </literal></entry>
+ </row>
+ <row>
+ <entry><literal>-</literal></entry>
<entry><type>integer</type></entry>
<entry>Delete the array element with specified index (Negative
integers count from the end). Throws an error if top level
diff --git a/src/backend/utils/adt/jsonfuncs.c b/src/backend/utils/adt/jsonfuncs.c
index 58c721c..d624fdb 100644
--- a/src/backend/utils/adt/jsonfuncs.c
+++ b/src/backend/utils/adt/jsonfuncs.c
@@ -3438,6 +3438,92 @@ jsonb_delete(PG_FUNCTION_ARGS)
}
/*
+ * SQL function jsonb_delete (jsonb, variadic text[])
+ *
+ * return a copy of the jsonb with the indicated items
+ * removed.
+ */
+Datum
+jsonb_delete_array(PG_FUNCTION_ARGS)
+{
+ Jsonb *in = PG_GETARG_JSONB(0);
+ ArrayType *keys = PG_GETARG_ARRAYTYPE_P(1);
+ Datum *keys_elems;
+ bool *keys_nulls;
+ int keys_len;
+ JsonbParseState *state = NULL;
+ JsonbIterator *it;
+ JsonbValue v,
+ *res = NULL;
+ bool skipNested = false;
+ JsonbIteratorToken r;
+
+ if (ARR_NDIM(keys) > 1)
+ ereport(ERROR,
+ (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+ errmsg("wrong number of array subscripts")));
+
+ if (JB_ROOT_IS_SCALAR(in))
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("cannot delete from scalar")));
+
+ if (JB_ROOT_COUNT(in) == 0)
+ PG_RETURN_JSONB(in);
+
+ deconstruct_array(keys, TEXTOID, -1, false, 'i',
+ &keys_elems, &keys_nulls, &keys_len);
+
+ if (keys_len == 0)
+ PG_RETURN_JSONB(in);
+
+ it = JsonbIteratorInit(&in->root);
+
+ while ((r = JsonbIteratorNext(&it, &v, skipNested)) != 0)
+ {
+ skipNested = true;
+
+ if ((r == WJB_ELEM || r == WJB_KEY) && v.type == jbvString)
+ {
+ int i;
+ bool found = false;
+
+ for (i = 0; i < keys_len; i++)
+ {
+ char *keyptr;
+ int keylen;
+
+ if (keys_nulls[i])
+ continue;
+
+ keyptr = VARDATA_ANY(keys_elems[i]);
+ keylen = VARSIZE_ANY_EXHDR(keys_elems[i]);
+ if (keylen == v.val.string.len &&
+ memcmp(keyptr, v.val.string.val, keylen) == 0)
+ {
+ found = true;
+ break;
+ }
+ }
+ if (found)
+ {
+ /* skip corresponding value as well */
+ if (r == WJB_KEY)
+ JsonbIteratorNext(&it, &v, true);
+
+ continue;
+ }
+ }
+
+ res = pushJsonbValue(&state, r, r < WJB_BEGIN_ARRAY ? &v : NULL);
+ }
+
+ Assert(res != NULL);
+
+ PG_RETURN_JSONB(JsonbValueToJsonb(res));
+}
+
+/*
* SQL function jsonb_delete (jsonb, int)
*
* return a copy of the jsonb with the indicated item
diff --git a/src/include/catalog/pg_operator.h b/src/include/catalog/pg_operator.h
index aeb7927..0be5e26 100644
--- a/src/include/catalog/pg_operator.h
+++ b/src/include/catalog/pg_operator.h
@@ -1820,6 +1820,8 @@ DATA(insert OID = 3284 ( "||" PGNSP PGUID b f f 3802 3802 3802 0 0 jsonb_con
DESCR("concatenate");
DATA(insert OID = 3285 ( "-" PGNSP PGUID b f f 3802 25 3802 0 0 3302 - - ));
DESCR("delete object field");
+DATA(insert OID = 3344 ( "-" PGNSP PGUID b f f 3802 1009 3802 0 0 3343 - -));
+DESCR("delete object fields");
DATA(insert OID = 3286 ( "-" PGNSP PGUID b f f 3802 23 3802 0 0 3303 - - ));
DESCR("delete array element");
DATA(insert OID = 3287 ( "#-" PGNSP PGUID b f f 3802 1009 3802 0 0 jsonb_delete_path - - ));
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 37e022d..be6cffd 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -4899,6 +4899,7 @@ DESCR("GIN support");
DATA(insert OID = 3301 ( jsonb_concat PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 3802 "3802 3802" _null_ _null_ _null_ _null_ _null_ jsonb_concat _null_ _null_ _null_ ));
DATA(insert OID = 3302 ( jsonb_delete PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 3802 "3802 25" _null_ _null_ _null_ _null_ _null_ jsonb_delete _null_ _null_ _null_ ));
DATA(insert OID = 3303 ( jsonb_delete PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 3802 "3802 23" _null_ _null_ _null_ _null_ _null_ jsonb_delete_idx _null_ _null_ _null_ ));
+DATA(insert OID = 3343 ( jsonb_delete PGNSP PGUID 12 1 0 25 0 f f f f t f i s 2 0 3802 "3802 1009" "{3802,1009}" "{i,v}" "{from_json,path_elems}" _null_ _null_ jsonb_delete_array _null_ _null_ _null_ ));
DATA(insert OID = 3304 ( jsonb_delete_path PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 3802 "3802 1009" _null_ _null_ _null_ _null_ _null_ jsonb_delete_path _null_ _null_ _null_ ));
DATA(insert OID = 3305 ( jsonb_set PGNSP PGUID 12 1 0 0 0 f f f f t f i s 4 0 3802 "3802 1009 3802 16" _null_ _null_ _null_ _null_ _null_ jsonb_set _null_ _null_ _null_ ));
DESCR("Set part of a jsonb");
diff --git a/src/include/utils/jsonb.h b/src/include/utils/jsonb.h
index ad24a98..b2607ad 100644
--- a/src/include/utils/jsonb.h
+++ b/src/include/utils/jsonb.h
@@ -404,6 +404,7 @@ extern Datum jsonb_concat(PG_FUNCTION_ARGS);
/* deletion */
extern Datum jsonb_delete(PG_FUNCTION_ARGS);
+extern Datum jsonb_delete_array(PG_FUNCTION_ARGS);
extern Datum jsonb_delete_idx(PG_FUNCTION_ARGS);
extern Datum jsonb_delete_path(PG_FUNCTION_ARGS);
diff --git a/src/test/regress/expected/jsonb.out b/src/test/regress/expected/jsonb.out
index e2cb08a..ba9b1d7 100644
--- a/src/test/regress/expected/jsonb.out
+++ b/src/test/regress/expected/jsonb.out
@@ -3095,6 +3095,24 @@ select '["a","b","c"]'::jsonb - -4;
["a", "b", "c"]
(1 row)
+select '{"a":1 , "b":2, "c":3}'::jsonb - '{b}'::text[];
+ ?column?
+------------------
+ {"a": 1, "c": 3}
+(1 row)
+
+select '{"a":1 , "b":2, "c":3}'::jsonb - '{c,b}'::text[];
+ ?column?
+----------
+ {"a": 1}
+(1 row)
+
+select '{"a":1 , "b":2, "c":3}'::jsonb - '{}'::text[];
+ ?column?
+--------------------------
+ {"a": 1, "b": 2, "c": 3}
+(1 row)
+
select jsonb_set('{"n":null, "a":1, "b":[1,2], "c":{"1":2}, "d":{"1":[2,3]}}'::jsonb, '{n}', '[1,2,3]');
jsonb_set
--------------------------------------------------------------------------
diff --git a/src/test/regress/sql/jsonb.sql b/src/test/regress/sql/jsonb.sql
index 6b4c796..eb65a38 100644
--- a/src/test/regress/sql/jsonb.sql
+++ b/src/test/regress/sql/jsonb.sql
@@ -777,6 +777,10 @@ select '["a","b","c"]'::jsonb - -2;
select '["a","b","c"]'::jsonb - -3;
select '["a","b","c"]'::jsonb - -4;
+select '{"a":1 , "b":2, "c":3}'::jsonb - '{b}'::text[];
+select '{"a":1 , "b":2, "c":3}'::jsonb - '{c,b}'::text[];
+select '{"a":1 , "b":2, "c":3}'::jsonb - '{}'::text[];
+
select jsonb_set('{"n":null, "a":1, "b":[1,2], "c":{"1":2}, "d":{"1":[2,3]}}'::jsonb, '{n}', '[1,2,3]');
select jsonb_set('{"n":null, "a":1, "b":[1,2], "c":{"1":2}, "d":{"1":[2,3]}}'::jsonb, '{b,-1}', '[1,2,3]');
select jsonb_set('{"n":null, "a":1, "b":[1,2], "c":{"1":2}, "d":{"1":[2,3]}}'::jsonb, '{d,1,0}', '[1,2,3]');
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