diff --git a/resources/3dcitydb/postgresql/sql-scripts/schema/datatype-instances.sql b/resources/3dcitydb/postgresql/sql-scripts/schema/datatype-instances.sql
index fc415b0..f308e31 100644
--- a/resources/3dcitydb/postgresql/sql-scripts/schema/datatype-instances.sql
+++ b/resources/3dcitydb/postgresql/sql-scripts/schema/datatype-instances.sql
@@ -3,7 +3,7 @@ DELETE FROM datatype;
 -- Core Module --
 
 INSERT INTO datatype (ID, SUPERTYPE_ID, TYPENAME, IS_ABSTRACT, NAMESPACE_ID, SCHEMA)
-VALUES (1, null, 'Undefined', 0, 1, '{"identifier":"core:Undefined","description":"Undefined is a fallback data type used to represent values that do not match any of the predefined types.","table":"property"}');
+VALUES (1, null, 'Undefined', 1, 1, '{"identifier":"core:Undefined","description":"Undefined data type.","table":"property"}');
 
 INSERT INTO datatype (ID, SUPERTYPE_ID, TYPENAME, IS_ABSTRACT, NAMESPACE_ID, SCHEMA)
 VALUES (2, null, 'Boolean', 0, 1, '{"identifier":"core:Boolean","description":"Boolean is a basic type and can have one of two values: true (represented as 1) or false (represented as 0).","table":"property","value":{"column":"val_int","type":"boolean"}}');
diff --git a/resources/3dcitydb/postgresql/sql-scripts/schema/objectclass-instances.sql b/resources/3dcitydb/postgresql/sql-scripts/schema/objectclass-instances.sql
index 6ae2e6a..9aaca4c 100644
--- a/resources/3dcitydb/postgresql/sql-scripts/schema/objectclass-instances.sql
+++ b/resources/3dcitydb/postgresql/sql-scripts/schema/objectclass-instances.sql
@@ -3,7 +3,7 @@ DELETE FROM objectclass;
 -- Core Module --
 
 INSERT INTO objectclass (ID, SUPERCLASS_ID, CLASSNAME, IS_ABSTRACT, IS_TOPLEVEL, NAMESPACE_ID, SCHEMA)
-VALUES (1, null, 'Undefined', 1, 0, 1, '{"identifier":"core:Undefined","description":"Undefined is a fallback class used to represent types that do not match any of the predefined classes.","table":"feature"}');
+VALUES (1, null, 'Undefined', 1, 0, 1, '{"identifier":"core:Undefined","description":"Undefined object class.","table":"feature"}');
 
 INSERT INTO objectclass (ID, SUPERCLASS_ID, CLASSNAME, IS_ABSTRACT, IS_TOPLEVEL, NAMESPACE_ID, SCHEMA)
 VALUES (2, null, 'AbstractObject', 1, 0, 1, '{"identifier":"core:AbstractObject","description":"AbstractObject is the abstract superclass of all feature and object types.","table":"feature","properties":[{"name":"id","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Specifies the internal database ID of the object.","value":{"column":"id","type":"integer"}},{"name":"objectId","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Specifies the identifier of the object that is unique within the database. Using a globally unique identifier is recommended.","value":{"column":"objectid","type":"string"}},{"name":"identifier","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Specifies an optional identifier of the object that is globally unique.","value":{"column":"identifier","type":"string"}},{"name":"codeSpace","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Specifies the code space of the identifier, typically a reference to the maintaining authority.","value":{"column":"identifier_codespace","type":"string"},"parent":1},{"name":"envelope","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Specifies the minimum bounding box that encloses the entire object.","value":{"column":"envelope","type":"core:Envelope"}},{"name":"objectClassId","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Specifies the internal object class ID of the object.","value":{"column":"objectclass_id","type":"integer"}},{"name":"lastModificationDate","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Indicates the date and time at which the object was last updated in the database.","value":{"column":"last_modification_date","type":"timestamp"}},{"name":"updatingPerson","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Specifies the person who last updated the object in the database.","value":{"column":"updating_person","type":"string"}},{"name":"reasonForUpdate","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Specifies the reason for the last update of the object in the database.","value":{"column":"reason_for_update","type":"string"}},{"name":"lineage","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Specifies the lineage information of the object.","value":{"column":"lineage","type":"string"}},{"name":"description","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Specifies a text description of the object.","type":"core:StringOrRef"},{"name":"descriptionReference","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Specifies a reference to a remote text description of the object.","type":"core:Reference"},{"name":"name","namespace":"http://3dcitydb.org/3dcitydb/core/5.0","description":"Specifies a label or identifier of the object, commonly a descriptive name.","type":"core:Code"}]}');