Entity framework TPT does not work - showstopper

Question

Greetings,
I'm experiencing a similar problem that is described here:
[Entity Framework and inheritance - Possible bug in EF?|http://stackoverflow.com/questions/11506683/entity-framework-and-inheritance-possible-bug-in-ef.]
I'm using:
Windows 7 64 bit
ODAC 11.2 Release 5 32 bit
Oracle Express 11.2 on localhost
Visual Studio 2012
Entity framework 5.0
.net 4.5
Create a simple database with TPT inheritance:
CREATE TABLE Person(
Id NUMBER(38, 0) NOT NULL,
Name VARCHAR2(50),
CONSTRAINT PK100 PRIMARY KEY (Id)
CREATE TABLE Employee(
Id NUMBER(38, 0) NOT NULL,
JobTitle VARCHAR2(50),
CONSTRAINT PK101 PRIMARY KEY (Id)
ALTER TABLE Employee ADD CONSTRAINT ref_Employee_person
FOREIGN KEY (Id)
REFERENCES Person(Id)
CREATE TABLE Superhero(
Id NUMBER(38, 0) NOT NULL,
Superpower VARCHAR2(50),
CONSTRAINT PK102 PRIMARY KEY (Id)
ALTER TABLE Superhero ADD CONSTRAINT ref_Superhero_person
FOREIGN KEY (Id)
REFERENCES Person(Id)
-- Sequence
CREATE SEQUENCE seq_id
INCREMENT BY 1
START WITH 55
MINVALUE 1
MAXVALUE 9999999999999999999999999999
NOCYCLE
NOORDER
CACHE 20
CREATE OR REPLACE TRIGGER PERSON_BI BEFORE INSERT ON PERSON FOR EACH ROW
BEGIN IF :NEW.ID IS NULL THEN SELECT SEQ_ID.NEXTVAL INTO :NEW.ID FROM DUAL; END IF; END;
Create a console application, add an edmx file, set up inheritance like so:
Diagram
And I set the Id property in Person entity as StoreGeneratedPattern to Identity
Then I created the following program:
static void Main(string[] args)
//Employee
var db = new Entities();
EMPLOYEE e = new EMPLOYEE() { ID = 0, JOBTITLE = "Programmer"};
e.NAME = "John Regular Doe";
db.People.Add(e);
//Superhero
SUPERHERO s = new SUPERHERO();
s.NAME = "Superman";
s.SUPERPOWER = "Flight";
db.People.Add(s);
db.SaveChanges();
//Fetch all persons and look at the type
//this is where I get an error:
var allPeople = db.People.ToList();
allPeople.ForEach(x => Console.WriteLine("type: " + x.GetType()));
This throws the following error when I fetch into allPeople:
All objects in the EntitySet 'Entities.People' must have unique primary keys. However, an instance of type 'TestingTPTInheritance.EMPLOYEE' and an instance of type 'TestingTPTInheritance.SUPERHERO' both have the same primary key value, 'EntitySet=People;ID=38'.
Looking at the database everything looks fine
-- Person table --
ID     NAME
39     John Regular Doe
40     Superman
-- Employee table --
ID     JOBTITLE
39     Programmer
-- Superhero table --
ID     SUPERPOWER
40     Flight
If I take the select that EF generates in " db.People.ToList();" and run it I get the following result:
C1      C2     NAME      C3      C4
0X0X     40     Superman           
0X0X     39     John Regular Doe     Programmer     
Is this a bug in ODAC. If so is there a workaround or will there be a fix soon?
Edited by: Amplus on 7.11.2012 07:59

Answer 1

Thank you for the reply shsu
I was being careless when I copied the error message and sequence, sorry about that. I did run this serveral times after I copied the error message. I recreate the seqence starting with 1 and recreated the problem. The error message is:
All objects in the EntitySet 'Entities.People' must have unique primary keys. However, an instance of type 'TestingTPTInheritance.EMPLOYEE' and an instance of type 'TestingTPTInheritance.SUPERHERO' both have the same primary key value, 'EntitySet=People;ID=2'.
The data in the tables is:
Person:
ID     NAME
1      John Regular Doe
2      Superman
employee
ID     JOBTITLE
1      Programmer
Superhero
ID     SUPERPOWER
2      Flight
And the generated select is:
SELECT
CASE WHEN (( NOT (("Project1"."C2" = 1) AND ("Project1"."C2" IS NOT NULL))) AND ( NOT (("Project2"."C2" = 1) AND ("Project2"."C2" IS NOT NULL)))) THEN '0X' WHEN (("Project1"."C2" = 1) AND ("Project1"."C2" IS NOT NULL)) THEN '0X0X' ELSE '0X1X' END AS "C1",
CAST( "Extent1"."ID" AS number(19,0)) AS "C2",
"Extent1"."NAME" AS "NAME",
CASE WHEN (( NOT (("Project1"."C2" = 1) AND ("Project1"."C2" IS NOT NULL))) AND ( NOT (("Project2"."C2" = 1) AND ("Project2"."C2" IS NOT NULL)))) THEN NULL WHEN (("Project1"."C2" = 1) AND ("Project1"."C2" IS NOT NULL)) THEN "Project1"."JOBTITLE" END AS "C3",
CASE WHEN (( NOT (("Project1"."C2" = 1) AND ("Project1"."C2" IS NOT NULL))) AND ( NOT (("Project2"."C2" = 1) AND ("Project2"."C2" IS NOT NULL)))) THEN NULL WHEN (("Project1"."C2" = 1) AND ("Project1"."C2" IS NOT NULL)) THEN NULL ELSE "Project2"."SUPERPOWER" END AS "C4"
FROM "TPT"."PERSON" "Extent1"
LEFT OUTER JOIN (SELECT
"Extent2"."JOBTITLE" AS "JOBTITLE",
CAST( "Extent2"."ID" AS number(19,0)) AS "C1",
1 AS "C2"
FROM "TPT"."EMPLOYEE" "Extent2" ) "Project1" ON ( CAST( "Extent1"."ID" AS number(19,0))) = "Project1"."C1"
LEFT OUTER JOIN (SELECT
"Extent3"."SUPERPOWER" AS "SUPERPOWER",
CAST( "Extent3"."ID" AS number(19,0)) AS "C1",
1 AS "C2"
FROM "TPT"."SUPERHERO" "Extent3" ) "Project2" ON ( CAST( "Extent1"."ID" AS number(19,0))) = "Project2"."C1"
With the following result:
C1      C2     NAME      C3      C4
0X0X     2      Superman      null      null --> should't there be a "Flight" entry here??
0X0X     1      John Regular Doe     Programmer     null
I also tried this:
var result1 = db.People.OfType<SUPERHERO>().ToList(); //Count=1
var result2 = db.People.OfType<EMPLOYEE>().ToList(); //Count=1
var result3 = db.People.OfType<PERSON>().ToList(); //Throws the following error:
All objects in the EntitySet 'Entities.People' must have unique primary keys. However, an instance of type 'TestingTPTInheritance.EMPLOYEE' and an instance of type 'TestingTPTInheritance.SUPERHERO' both have the same primary key value, 'EntitySet=People;ID=2'.
The only thing I can think of is that my little console app is picking up the oracle client from oracle express instead of the ODAC driver. Is there an easy way to force it to use the correct driver? I have this in my config file but I'm not sure if it works:
<oracle.dataaccess.client>
<settings>
<add name="DllPath" value="C:\oracle\product\11.2.0\client_3\bin" />
</settings>
</oracle.dataaccess.client>
And I have also referenced Oracle.Data.Access here:
C:\oracle\product\11.2.0\client_3\odp.net\bin\4\Oracle.DataAccess.dll
client_3 directory is my ODAC Release 5 installation. I changed the config settings to:
<oracle.dataaccess.client>
<settings>
<add name="DllPath" value="C:\oracle\product\11.2.0\client_3\odp.net\bin\4\Oracle.DataAccess.dll" />
</settings>
</oracle.dataaccess.client>
then the program was able to run this line:
var allPeople = db.People.ToList();
But both objects were of type EMPLOYEE. Then I ran this:
var result1 = db.People.OfType<SUPERHERO>().ToList();
and get the following error:
All objects in the EntitySet 'Entities.People' must have unique primary keys. However, an instance of type 'TestingTPTInheritance.EMPLOYEE' and an instance of type 'TestingTPTInheritance.SUPERHERO' both have the same primary key value, 'EntitySet=People;ID=2'.
The problem must be that I do have multiple versions of Oracle client installed on my computer and it is picking up the wrong one either when I'm generating the edmx file or when the application is connecting to the db. I think my next step will be to uninstall all oracle client instances as well as oracle express and try again from scratch!!