Add casts from jsonb

Add explicit cast from scalar jsonb to all numeric and bool types. It would be
better to have cast from scalar jsonb to text too but there is already a cast
from jsonb to text as just text representation of json. There is no way to have
two different casts for the same type's pair.

Bump catalog version

Author: Anastasia Lubennikova with editorization by Nikita Glukhov and me
Review by: Aleksander Alekseev, Nikita Glukhov, Darafei Praliaskouski
Discussion: https://www.postgresql.org/message-id/flat/0154d35a-24ae-f063-5273-9ffcdf1c7f2e@postgrespro.ru

diff --git a/src/backend/utils/adt/jsonb.c b/src/backend/utils/adt/jsonb.c
index 0f701801641aa8bc696f8917f8491be303faab75..80d23cc0524cdb8ac6ce50bd91a1c7539a2367d7 100644 (file)
--- a/src/backend/utils/adt/jsonb.c
+++ b/src/backend/utils/adt/jsonb.c
@@ -1845,3 +1845,178 @@ jsonb_object_agg_finalfn(PG_FUNCTION_ARGS)
 
        PG_RETURN_POINTER(out);
 }
+
+
+/*
+ * Extract scalar value from raw-scalar pseudo-array jsonb.
+ */
+static JsonbValue *
+JsonbExtractScalar(JsonbContainer *jbc, JsonbValue *res)
+{
+       JsonbIterator *it;
+       JsonbIteratorToken tok PG_USED_FOR_ASSERTS_ONLY;
+       JsonbValue      tmp;
+
+       if (!JsonContainerIsArray(jbc) || !JsonContainerIsScalar(jbc))
+               return NULL;
+
+       /*
+        * A root scalar is stored as an array of one element, so we get the
+        * array and then its first (and only) member.
+        */
+       it = JsonbIteratorInit(jbc);
+
+       tok = JsonbIteratorNext(&it, &tmp, true);
+       Assert(tok == WJB_BEGIN_ARRAY);
+       Assert(tmp.val.array.nElems == 1 && tmp.val.array.rawScalar);
+
+       tok = JsonbIteratorNext(&it, res, true);
+       Assert (tok == WJB_ELEM);
+       Assert(IsAJsonbScalar(res));
+
+       tok = JsonbIteratorNext(&it, &tmp, true);
+       Assert (tok == WJB_END_ARRAY);
+
+       tok = JsonbIteratorNext(&it, &tmp, true);
+       Assert(tok == WJB_DONE);
+
+       return res;
+}
+
+Datum
+jsonb_bool(PG_FUNCTION_ARGS)
+{
+       Jsonb      *in = PG_GETARG_JSONB_P(0);
+       JsonbValue      v;
+
+       if (!JsonbExtractScalar(&in->root, &v) || v.type != jbvBool)
+               ereport(ERROR,
+                               (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+                                errmsg("jsonb value must be boolean")));
+
+       PG_FREE_IF_COPY(in, 0);
+
+       PG_RETURN_BOOL(v.val.boolean);
+}
+
+Datum
+jsonb_numeric(PG_FUNCTION_ARGS)
+{
+       Jsonb      *in = PG_GETARG_JSONB_P(0);
+       JsonbValue      v;
+       Numeric         retValue;
+
+       if (!JsonbExtractScalar(&in->root, &v) || v.type != jbvNumeric)
+               ereport(ERROR,
+                               (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+                                errmsg("jsonb value must be numeric")));
+
+       /*
+        * v.val.numeric points into jsonb body, so we need to make a copy to return
+        */
+       retValue = DatumGetNumericCopy(NumericGetDatum(v.val.numeric));
+
+       PG_FREE_IF_COPY(in, 0);
+
+       PG_RETURN_NUMERIC(retValue);
+}
+
+Datum
+jsonb_int2(PG_FUNCTION_ARGS)
+{
+       Jsonb      *in = PG_GETARG_JSONB_P(0);
+       JsonbValue  v;
+       Datum           retValue;
+
+       if (!JsonbExtractScalar(&in->root, &v) || v.type != jbvNumeric)
+               ereport(ERROR,
+                               (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+                                errmsg("jsonb value must be numeric")));
+
+       retValue = DirectFunctionCall1(numeric_int2,
+                                                                  NumericGetDatum(v.val.numeric));
+
+       PG_FREE_IF_COPY(in, 0);
+
+       PG_RETURN_DATUM(retValue);
+}
+
+Datum
+jsonb_int4(PG_FUNCTION_ARGS)
+{
+       Jsonb      *in = PG_GETARG_JSONB_P(0);
+       JsonbValue  v;
+       Datum           retValue;
+
+       if (!JsonbExtractScalar(&in->root, &v) || v.type != jbvNumeric)
+               ereport(ERROR,
+                               (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+                                errmsg("jsonb value must be numeric")));
+
+       retValue = DirectFunctionCall1(numeric_int4,
+                                                                  NumericGetDatum(v.val.numeric));
+
+       PG_FREE_IF_COPY(in, 0);
+
+       PG_RETURN_DATUM(retValue);
+}
+
+Datum
+jsonb_int8(PG_FUNCTION_ARGS)
+{
+       Jsonb      *in = PG_GETARG_JSONB_P(0);
+       JsonbValue  v;
+       Datum           retValue;
+
+       if (!JsonbExtractScalar(&in->root, &v) || v.type != jbvNumeric)
+               ereport(ERROR,
+                               (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+                                errmsg("jsonb value must be numeric")));
+
+       retValue = DirectFunctionCall1(numeric_int8,
+                                                                  NumericGetDatum(v.val.numeric));
+
+       PG_FREE_IF_COPY(in, 0);
+
+       PG_RETURN_DATUM(retValue);
+}
+
+Datum
+jsonb_float4(PG_FUNCTION_ARGS)
+{
+       Jsonb      *in = PG_GETARG_JSONB_P(0);
+       JsonbValue      v;
+       Datum           retValue;
+
+       if (!JsonbExtractScalar(&in->root, &v) || v.type != jbvNumeric)
+               ereport(ERROR,
+                               (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+                                errmsg("jsonb value must be numeric")));
+
+       retValue = DirectFunctionCall1(numeric_float4,
+                                                                  NumericGetDatum(v.val.numeric));
+
+       PG_FREE_IF_COPY(in, 0);
+
+       PG_RETURN_DATUM(retValue);
+}
+
+Datum
+jsonb_float8(PG_FUNCTION_ARGS)
+{
+       Jsonb      *in = PG_GETARG_JSONB_P(0);
+       JsonbValue      v;
+       Datum           retValue;
+
+       if (!JsonbExtractScalar(&in->root, &v) || v.type != jbvNumeric)
+               ereport(ERROR,
+                               (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+                                errmsg("jsonb value must be numeric")));
+
+       retValue = DirectFunctionCall1(numeric_float8,
+                                                                  NumericGetDatum(v.val.numeric));
+
+       PG_FREE_IF_COPY(in, 0);
+
+       PG_RETURN_DATUM(retValue);
+}

diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index bfc2bd125d731ee6e075d4cfc83567d60a8f1ea9..d4a7b23f80121a93abacc5792f586d628fb06121 100644 (file)
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -53,6 +53,6 @@
  */
 
 /*                                                     yyyymmddN */
-#define CATALOG_VERSION_NO     201803271
+#define CATALOG_VERSION_NO     201803291
 
 #endif

diff --git a/src/include/catalog/pg_cast.h b/src/include/catalog/pg_cast.h
index b4478188caba8f5b4320a5efa4d3c5415fbb594b..c47fb5bd0ddf09c85ee51186e9c8c3389a926448 100644 (file)
--- a/src/include/catalog/pg_cast.h
+++ b/src/include/catalog/pg_cast.h
@@ -392,4 +392,13 @@ DATA(insert ( 1700 1700 1703 i f ));
 DATA(insert (  114 3802    0 a i ));
 DATA(insert ( 3802     114    0 a i ));
 
+/* jsonb to numeric and bool types */
+DATA(insert ( 3802     16       3556 e f ));
+DATA(insert ( 3802     1700 3449 e f ));
+DATA(insert ( 3802     21   3450 e f ));
+DATA(insert ( 3802     23   3451 e f ));
+DATA(insert ( 3802     20   3452 e f ));
+DATA(insert ( 3802     700  3453 e f ));
+DATA(insert ( 3802     701  2580 e f ));
+
 #endif                                                 /* PG_CAST_H */

diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index bfc90098f8671a1bac7eb4866ee54d578974f668..ec50afcdf000be1f9af6ecf476776f2d6f20f9ba 100644 (file)
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2475,6 +2475,22 @@ DESCR("convert int2 to numeric");
 DATA(insert OID = 1783 ( int2                                  PGNSP PGUID 12 1 0 0 0 f f f t f i s 1 0 21 "1700" _null_ _null_ _null_ _null_ _null_ numeric_int2 _null_ _null_ _null_ ));
 DESCR("convert numeric to int2");
 
+
+DATA(insert OID = 3556 ( bool                          PGNSP PGUID 12 1 0 0 0 f f f t f i s 1 0 16 "3802" _null_ _null_ _null_ _null_ _null_ jsonb_bool  _null_ _null_ _null_ ));
+DESCR("convert jsonb to boolean");
+DATA(insert OID = 3449 ( numeric                       PGNSP PGUID 12 1 0 0 0 f f f t f i s 1 0 1700 "3802" _null_ _null_ _null_ _null_ _null_ jsonb_numeric  _null_ _null_ _null_ ));
+DESCR("convert jsonb to numeric");
+DATA(insert OID = 3450 ( int2                          PGNSP PGUID 12 1 0 0 0 f f f t f i s 1 0 21 "3802" _null_ _null_ _null_ _null_ _null_ jsonb_int2  _null_ _null_ _null_ ));
+DESCR("convert jsonb to int2");
+DATA(insert OID = 3451 ( int4                          PGNSP PGUID 12 1 0 0 0 f f f t f i s 1 0 23 "3802" _null_ _null_ _null_ _null_ _null_ jsonb_int4  _null_ _null_ _null_ ));
+DESCR("convert jsonb to int4");
+DATA(insert OID = 3452 ( int8                          PGNSP PGUID 12 1 0 0 0 f f f t f i s 1 0 20 "3802" _null_ _null_ _null_ _null_ _null_ jsonb_int8  _null_ _null_ _null_ ));
+DESCR("convert jsonb to int8");
+DATA(insert OID = 3453 ( float4                                PGNSP PGUID 12 1 0 0 0 f f f t f i s 1 0 700 "3802" _null_ _null_ _null_ _null_ _null_ jsonb_float4  _null_ _null_ _null_ ));
+DESCR("convert jsonb to float4");
+DATA(insert OID = 2580 ( float8                                PGNSP PGUID 12 1 0 0 0 f f f t f i s 1 0 701 "3802" _null_ _null_ _null_ _null_ _null_ jsonb_float8  _null_ _null_ _null_ ));
+DESCR("convert jsonb to float8");
+
 /* formatting */
 DATA(insert OID = 1770 ( to_char                       PGNSP PGUID 12 1 0 0 0 f f f t f s s 2 0 25 "1184 25" _null_ _null_ _null_ _null_  _null_ timestamptz_to_char _null_ _null_ _null_ ));
 DESCR("format timestamp with time zone to text");

diff --git a/src/test/regress/expected/jsonb.out b/src/test/regress/expected/jsonb.out
index 465195a3172a40137b9d4715a54bc24ea0d425d2..f8d6e6f7ccd17104752ed5dee7393a7eed6aaf8b 100644 (file)
--- a/src/test/regress/expected/jsonb.out
+++ b/src/test/regress/expected/jsonb.out
@@ -4191,3 +4191,108 @@ select ts_headline('[]'::jsonb, tsquery('aaa & bbb'));
  []
 (1 row)
 
+-- casts
+select 'true'::jsonb::bool;
+ bool 
+------
+ t
+(1 row)
+
+select '[]'::jsonb::bool;
+ERROR:  jsonb value must be boolean
+select '1.0'::jsonb::float;
+ float8 
+--------
+      1
+(1 row)
+
+select '[1.0]'::jsonb::float;
+ERROR:  jsonb value must be numeric
+select '12345'::jsonb::int4;
+ int4  
+-------
+ 12345
+(1 row)
+
+select '"hello"'::jsonb::int4;
+ERROR:  jsonb value must be numeric
+select '12345'::jsonb::numeric;
+ numeric 
+---------
+   12345
+(1 row)
+
+select '{}'::jsonb::numeric;
+ERROR:  jsonb value must be numeric
+select '12345.05'::jsonb::numeric;
+ numeric  
+----------
+ 12345.05
+(1 row)
+
+select '12345.05'::jsonb::float4;
+ float4 
+--------
+  12345
+(1 row)
+
+select '12345.05'::jsonb::float8;
+  float8  
+----------
+ 12345.05
+(1 row)
+
+select '12345.05'::jsonb::int2;
+ int2  
+-------
+ 12345
+(1 row)
+
+select '12345.05'::jsonb::int4;
+ int4  
+-------
+ 12345
+(1 row)
+
+select '12345.05'::jsonb::int8;
+ int8  
+-------
+ 12345
+(1 row)
+
+select '12345.0000000000000000000000000000000000000000000005'::jsonb::numeric;
+                       numeric                        
+------------------------------------------------------
+ 12345.0000000000000000000000000000000000000000000005
+(1 row)
+
+select '12345.0000000000000000000000000000000000000000000005'::jsonb::float4;
+ float4 
+--------
+  12345
+(1 row)
+
+select '12345.0000000000000000000000000000000000000000000005'::jsonb::float8;
+ float8 
+--------
+  12345
+(1 row)
+
+select '12345.0000000000000000000000000000000000000000000005'::jsonb::int2;
+ int2  
+-------
+ 12345
+(1 row)
+
+select '12345.0000000000000000000000000000000000000000000005'::jsonb::int4;
+ int4  
+-------
+ 12345
+(1 row)
+
+select '12345.0000000000000000000000000000000000000000000005'::jsonb::int8;
+ int8  
+-------
+ 12345
+(1 row)
+

diff --git a/src/test/regress/sql/jsonb.sql b/src/test/regress/sql/jsonb.sql
index 903e5ef67d868c5b60c7a94a5c7793e8a90ad5d4..2439f949bd51793a34d087bfa62f98e14c11c0a2 100644 (file)
--- a/src/test/regress/sql/jsonb.sql
+++ b/src/test/regress/sql/jsonb.sql
@@ -1105,3 +1105,25 @@ select ts_headline('english', '{"a": "aaa bbb", "b": {"c": "ccc ddd fff", "c1":
 select ts_headline('null'::jsonb, tsquery('aaa & bbb'));
 select ts_headline('{}'::jsonb, tsquery('aaa & bbb'));
 select ts_headline('[]'::jsonb, tsquery('aaa & bbb'));
+
+-- casts
+select 'true'::jsonb::bool;
+select '[]'::jsonb::bool;
+select '1.0'::jsonb::float;
+select '[1.0]'::jsonb::float;
+select '12345'::jsonb::int4;
+select '"hello"'::jsonb::int4;
+select '12345'::jsonb::numeric;
+select '{}'::jsonb::numeric;
+select '12345.05'::jsonb::numeric;
+select '12345.05'::jsonb::float4;
+select '12345.05'::jsonb::float8;
+select '12345.05'::jsonb::int2;
+select '12345.05'::jsonb::int4;
+select '12345.05'::jsonb::int8;
+select '12345.0000000000000000000000000000000000000000000005'::jsonb::numeric;
+select '12345.0000000000000000000000000000000000000000000005'::jsonb::float4;
+select '12345.0000000000000000000000000000000000000000000005'::jsonb::float8;
+select '12345.0000000000000000000000000000000000000000000005'::jsonb::int2;
+select '12345.0000000000000000000000000000000000000000000005'::jsonb::int4;
+select '12345.0000000000000000000000000000000000000000000005'::jsonb::int8;