Add Oracle object pretty-printing example.

Author: anthony-tuininga

doc/src/release_notes.rst

@@ -27,7 +27,7 @@ Thin Mode Changes
 Common Changes
 ++++++++++++++
 
-#)  Improved test suite.
+#)  Improved test suite and samples.
 
 
 oracledb 1.3.0 (March 2023)

samples/insert_geometry.py

@@ -1,5 +1,5 @@
 #------------------------------------------------------------------------------
-# Copyright (c) 2016, 2022, Oracle and/or its affiliates.
+# Copyright (c) 2016, 2023, Oracle and/or its affiliates.
 #
 # Portions Copyright 2007-2015, Anthony Tuininga. All rights reserved.
 #
@@ -58,25 +58,7 @@
 print("Created object", obj)
 
 with connection.cursor() as cursor:
-
-    # create sample table
-    cursor.execute("""
-        begin
-          begin
-            execute immediate 'drop table TestGeometry';
-          exception
-          when others then
-            if sqlcode <> -942 then
-              raise;
-            end if;
-          end;
-
-          execute immediate 'create table TestGeometry (
-                                 IntCol number(9) not null,
-                                 Geometry MDSYS.SDO_GEOMETRY)';
-        end;""")
-
-
+    cursor.execute("truncate table TestGeometry")
     print("Adding row to table...")
     cursor.execute("insert into TestGeometry values (1, :objbv)", objbv=obj)
     connection.commit()

samples/object_dump.py

@@ -0,0 +1,106 @@
+#------------------------------------------------------------------------------
+# Copyright (c) 2023, Oracle and/or its affiliates.
+#
+# This software is dual-licensed to you under the Universal Permissive License
+# (UPL) 1.0 as shown at https://oss.oracle.com/licenses/upl and Apache License
+# 2.0 as shown at http://www.apache.org/licenses/LICENSE-2.0. You may choose
+# either license.
+#
+# If you elect to accept the software under the Apache License, Version 2.0,
+# the following applies:
+#
+# Licensed 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
+#
+#    https://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.
+#------------------------------------------------------------------------------
+
+#------------------------------------------------------------------------------
+# object_dump.py
+#
+# Shows how to pretty-print an Oracle object or collection.
+# Also shows how to insert a Python object to an Oracle object column.
+#------------------------------------------------------------------------------
+
+import oracledb
+import sample_env
+
+# determine whether to use python-oracledb thin mode or thick mode
+if not sample_env.get_is_thin():
+    oracledb.init_oracle_client(lib_dir=sample_env.get_oracle_client())
+
+# Create Oracle connection and cursor objects
+connection = oracledb.connect(user=sample_env.get_main_user(),
+                              password=sample_env.get_main_password(),
+                              dsn=sample_env.get_connect_string())
+cursor = connection.cursor()
+
+# Create a Python class equivalent to an Oracle SDO object
+class MySDO(object):
+
+    def __init__(self, gtype, elem_info, ordinates):
+        self.gtype = gtype
+        self.elem_info = elem_info
+        self.ordinates = ordinates
+
+
+# Get Oracle type information
+obj_type = connection.gettype("MDSYS.SDO_GEOMETRY")
+element_info_type_obj = connection.gettype("MDSYS.SDO_ELEM_INFO_ARRAY")
+ordinate_type_obj = connection.gettype("MDSYS.SDO_ORDINATE_ARRAY")
+
+# Convert a Python object to MDSYS.SDO_GEOMETRY
+def sdo_input_type_handler(cursor, value, num_elements):
+    def sdo_in_converter(value):
+        obj = obj_type.newobject()
+        obj.SDO_GTYPE = value.gtype
+        obj.SDO_ELEM_INFO = element_info_type_obj.newobject()
+        obj.SDO_ELEM_INFO.extend(value.elem_info)
+        obj.SDO_ORDINATES = ordinate_type_obj.newobject()
+        obj.SDO_ORDINATES.extend(value.ordinates)
+        return obj
+
+    if isinstance(value, MySDO):
+        return cursor.var(obj_type, arraysize=num_elements,
+                          inconverter=sdo_in_converter)
+
+
+# Create and insert a Python object
+sdo = MySDO(2003, [1, 1003, 3], [1, 1, 5, 7])
+cursor.inputtypehandler = sdo_input_type_handler
+cursor.execute("truncate table TestGeometry")
+cursor.execute("insert into TestGeometry values (1, :1)", [sdo])
+
+
+# Define a function to pretty-print the contents of an Oracle object
+def dump_object(obj, prefix=""):
+    if obj.type.iscollection:
+        print(f"{prefix}[")
+        for value in obj.aslist():
+            if isinstance(value, oracledb.DbObject):
+                dump_object(value, prefix + "  ")
+            else:
+                print(f"{prefix}  {repr(value)}")
+        print(f"{prefix}]")
+    else:
+        print(f"{prefix}{{")
+        for attr in obj.type.attributes:
+            value = getattr(obj, attr.name)
+            if isinstance(value, oracledb.DbObject):
+                print(f"{prefix}  {attr.name}:")
+                dump_object(value, prefix + "    ")
+            else:
+                print(f"{prefix}  {attr.name}: {repr(value)}")
+        print(f"{prefix}}}")
+
+# Query the row back
+cursor.execute("select geometry from TestGeometry")
+for (obj,) in cursor:
+    dump_object(obj)

samples/sql/create_schema.sql

@@ -1,5 +1,5 @@
 /*-----------------------------------------------------------------------------
- * Copyright 2017, 2022, Oracle and/or its affiliates.
+ * Copyright 2017, 2023, Oracle and/or its affiliates.
  *
  * This software is dual-licensed to you under the Universal Permissive License
  * (UPL) 1.0 as shown at https://oss.oracle.com/licenses/upl and Apache License
@@ -245,6 +245,12 @@ create table &main_user..LoadCsvTab (
 )
 /
 
+create table &main_user..TestGeometry (
+    id                    number(9) not null,
+    geometry              mdsys.sdo_geometry not null
+)
+/
+
 declare
     t_Version                           number;
 begin