Implement array version of jsonb_delete and operator

This makes it possible to delete multiple keys from a jsonb value by
passing in an array of text values, which makes the operaiton much
faster than individually deleting the keys (which would require copying
the jsonb structure over and over again.

Reviewed by Dmitry Dolgov and Michael Paquier

doc/src/sgml/func.sgml

@@ -10843,6 +10843,14 @@ table2-mapping
         on their key value.</entry>
         <entry><literal>'{"a": "b"}'::jsonb - 'a' </literal></entry>
        </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>

src/backend/utils/adt/jsonfuncs.c

@@ -3437,6 +3437,92 @@ jsonb_delete(PG_FUNCTION_ARGS)
 	PG_RETURN_JSONB(JsonbValueToJsonb(res));
 }
 
+/*
+ * 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)
  *

src/include/catalog/pg_operator.h

@@ -1826,6 +1826,8 @@ 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 = 3398 (  "-"      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 - - ));

src/include/catalog/pg_proc.h

@@ -957,7 +957,7 @@ DESCR("name of the current database");
 DATA(insert OID = 817 (  current_query		  PGNSP PGUID 12 1 0 0 0 f f f f f f v r 0 0 25 "" _null_ _null_ _null_ _null_	_null_ current_query _null_ _null_ _null_ ));
 DESCR("get the currently executing query");
 
-DATA(insert OID = 3343 (  int8_mul_cash		   PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 790 "20 790" _null_ _null_ _null_ _null_ _null_ int8_mul_cash _null_ _null_ _null_ ));
+DATA(insert OID = 3399 (  int8_mul_cash		   PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 790 "20 790" _null_ _null_ _null_ _null_ _null_ int8_mul_cash _null_ _null_ _null_ ));
 DATA(insert OID =  862 (  int4_mul_cash		   PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 790 "23 790" _null_ _null_ _null_ _null_ _null_ int4_mul_cash _null_ _null_ _null_ ));
 DATA(insert OID =  863 (  int2_mul_cash		   PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 790 "21 790" _null_ _null_ _null_ _null_ _null_ int2_mul_cash _null_ _null_ _null_ ));
 DATA(insert OID = 3344 (  cash_mul_int8		   PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 790 "790 20" _null_ _null_ _null_ _null_ _null_ cash_mul_int8 _null_ _null_ _null_ ));
@@ -4903,6 +4903,7 @@ 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");

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                                 
 --------------------------------------------------------------------------

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]');