feat(c/driver/postgresql): add POSTGRESQL:type metadata

c/driver/postgresql/postgres_type.h

@@ -354,6 +354,11 @@ class PostgresType {
         break;
     }
 
+    // Don't add POSTGRESQL:type to top-level field (which is the schema)
+    if (type_id_ != PostgresTypeId::kRecord || !field_name_.empty()) {
+      NANOARROW_RETURN_NOT_OK(AddTypeMetadata(schema));
+    }
+
     NANOARROW_RETURN_NOT_OK(ArrowSchemaSetName(schema, field_name_.c_str()));
     return NANOARROW_OK;
   }
@@ -370,12 +375,25 @@ class PostgresType {
   std::vector<PostgresType> children_;
 
   static constexpr const char* kPostgresTypeKey = "ADBC:postgresql:typname";
+  static constexpr const char* kTypeKey = "POSTGRESQL:type";
   static constexpr const char* kExtensionName = "ARROW:extension:name";
   static constexpr const char* kOpaqueExtensionName = "arrow.opaque";
   static constexpr const char* kJsonExtensionName = "arrow.json";
   static constexpr const char* kUuidExtensionName = "arrow.uuid";
   static constexpr const char* kExtensionMetadata = "ARROW:extension:metadata";
 
+  ArrowErrorCode AddTypeMetadata(ArrowSchema* schema) const {
+    const char* typname =
+        !typname_.empty() ? typname_.c_str() : PostgresTypname(type_id_);
+    nanoarrow::UniqueBuffer buffer;
+    NANOARROW_RETURN_NOT_OK(ArrowMetadataBuilderInit(buffer.get(), schema->metadata));
+    NANOARROW_RETURN_NOT_OK(ArrowMetadataBuilderAppend(
+        buffer.get(), ArrowCharView(kTypeKey), ArrowCharView(typname)));
+    NANOARROW_RETURN_NOT_OK(
+        ArrowSchemaSetMetadata(schema, reinterpret_cast<char*>(buffer->data)));
+    return NANOARROW_OK;
+  }
+
   ArrowErrorCode AddPostgresTypeMetadata(ArrowSchema* schema,
                                          const std::string& vendor_name) const {
     // the typname_ may not always be set: an instance of this class can be

c/driver/postgresql/postgres_type_test.cc

@@ -221,6 +221,11 @@ TEST(PostgresTypeTest, PostgresTypeSetSchema) {
                         &typnameMetadataValue);
   EXPECT_EQ(std::string(typnameMetadataValue.data, typnameMetadataValue.size_bytes),
             "numeric");
+  typnameMetadataValue = ArrowCharView("<not found>");
+  ArrowMetadataGetValue(schema->metadata, ArrowCharView("POSTGRESQL:type"),
+                        &typnameMetadataValue);
+  EXPECT_EQ(std::string(typnameMetadataValue.data, typnameMetadataValue.size_bytes),
+            "numeric");
   ArrowMetadataGetValue(schema->metadata, ArrowCharView("ARROW:extension:name"),
                         &typnameMetadataValue);
   EXPECT_EQ(std::string(typnameMetadataValue.data, typnameMetadataValue.size_bytes),
@@ -241,6 +246,11 @@ TEST(PostgresTypeTest, PostgresTypeSetSchema) {
                         ArrowCharView("ADBC:postgresql:typname"), &typnameMetadataValue);
   EXPECT_EQ(std::string(typnameMetadataValue.data, typnameMetadataValue.size_bytes),
             "numeric");
+  typnameMetadataValue = ArrowCharView("<not found>");
+  ArrowMetadataGetValue(schema->children[0]->metadata, ArrowCharView("POSTGRESQL:type"),
+                        &typnameMetadataValue);
+  EXPECT_EQ(std::string(typnameMetadataValue.data, typnameMetadataValue.size_bytes),
+            "numeric");
   schema.reset();
 
   ArrowSchemaInit(schema.get());
@@ -267,6 +277,11 @@ TEST(PostgresTypeTest, PostgresTypeSetSchema) {
                         &typnameMetadataValue);
   EXPECT_EQ(std::string(typnameMetadataValue.data, typnameMetadataValue.size_bytes),
             "some_name");
+  typnameMetadataValue = ArrowCharView("<not found>");
+  ArrowMetadataGetValue(schema->metadata, ArrowCharView("POSTGRESQL:type"),
+                        &typnameMetadataValue);
+  EXPECT_EQ(std::string(typnameMetadataValue.data, typnameMetadataValue.size_bytes),
+            "some_name");
   schema.reset();
 }
 

c/driver/postgresql/result_reader.cc

@@ -203,9 +203,8 @@ Status PqResultArrayReader::Initialize(int64_t* rows_affected) {
     UNWRAP_ERRNO(Internal,
                  type_resolver_->FindWithDefault(helper_.FieldType(i), &child_type));
 
+    child_type = child_type.WithFieldName(helper_.FieldName(i));
     UNWRAP_ERRNO(Internal, child_type.SetSchema(schema_->children[i], vendor_name_));
-    UNWRAP_ERRNO(Internal,
-                 ArrowSchemaSetName(schema_->children[i], helper_.FieldName(i)));
 
     std::unique_ptr<PostgresCopyFieldReader> child_reader;
     UNWRAP_NANOARROW(

c/driver/postgresql/validation/queries/type/bind/binary.txtcase

@@ -0,0 +1,31 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// part: metadata
+
+[tags]
+sql-type-name = "bytea"
+
+// part: setup_query
+
+CREATE TABLE test_binary (
+    res BYTEA
+);
+
+// part: bind_query
+
+INSERT INTO test_binary (res) VALUES ($1)

c/driver/postgresql/validation/queries/type/bind/binary_view.txtcase

@@ -0,0 +1,27 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// part: metadata
+
+[tags]
+sql-type-name = "bytea"
+
+// part: setup_query
+
+CREATE TABLE test_binary_view (
+    res BYTEA
+);

c/driver/postgresql/validation/queries/type/bind/boolean.txtcase

@@ -0,0 +1,21 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// part: metadata
+
+[tags]
+sql-type-name = "bool"

c/driver/postgresql/validation/queries/type/bind/date.txtcase

@@ -0,0 +1,21 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// part: metadata
+
+[tags]
+sql-type-name = "date"

c/driver/postgresql/validation/queries/type/bind/decimal.txtcase

@@ -15,6 +15,11 @@
 // specific language governing permissions and limitations
 // under the License.
 
+// part: metadata
+
+[tags]
+sql-type-name = "numeric"
+
 // part: expected_schema
 {
     "format": "+s",

c/driver/postgresql/validation/queries/type/bind/fixed_size_binary.txtcase

@@ -0,0 +1,27 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// part: metadata
+
+[tags]
+sql-type-name = "bytea"
+
+// part: setup_query
+
+CREATE TABLE test_fixed_size_binary (
+    res BYTEA
+);

c/driver/postgresql/validation/queries/type/bind/float16.txtcase

@@ -0,0 +1,22 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// part: metadata
+
+[tags]
+sql-type-name = "real"
+field-type-name = "float4"

c/driver/postgresql/validation/queries/type/bind/float32.txtcase

@@ -0,0 +1,22 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// part: metadata
+
+[tags]
+sql-type-name = "real"
+field-type-name = "float4"

c/driver/postgresql/validation/queries/type/bind/float64.txtcase

@@ -0,0 +1,22 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// part: metadata
+
+[tags]
+sql-type-name = "double precision"
+field-type-name = "float8"

c/driver/postgresql/validation/queries/type/bind/int16.txtcase

@@ -0,0 +1,22 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// part: metadata
+
+[tags]
+sql-type-name = "smallint"
+field-type-name = "int2"

c/driver/postgresql/validation/queries/type/bind/int32.txtcase

@@ -0,0 +1,22 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// part: metadata
+
+[tags]
+sql-type-name = "integer"
+field-type-name = "int4"

c/driver/postgresql/validation/queries/type/bind/int64.txtcase

@@ -0,0 +1,22 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// part: metadata
+
+[tags]
+sql-type-name = "bigint"
+field-type-name = "int8"