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OracleDataTable -> Constrained to be unique error.
Posted: Mon 05 May 2008 19:53
by zguven
I recieve this error:
Column 'TESTFIELD' is constrained to be unique error. Value '' is already present.
but value is NULL, not ''.
I use OracleDataTable. OraDirect.Net v 4.6, Oracle 10.2.01, VS 2005
Column constraint defined in oracle :
alter table TESTTABLE
add constraint UQ_TEST unique (TESTFIELD);
Best Regards.
Zeki Güven.
Posted: Tue 06 May 2008 11:25
by Alexey.mdr
Hello Zeki,
You are receiving this error because for Oracle server
NULL and '' (Empty string) are the same.
Posted: Tue 06 May 2008 11:42
by zguven
Problem with your OracleDataTable component. Its running in delphi with TOraQuery without any problem.
It's not a oracle problem.
Posted: Tue 06 May 2008 11:43
by Alexey.mdr
Please send me (alexeyman*crlab*com) a small test project to reproduce the problem.
It is desirable to use 'test' schema objects, otherwise include the
definition of your own database objects.
Do not use third party components.
If it is impossible for you to create the test project, send us a piece of
your code where the error occurs.
Posted: Tue 06 May 2008 12:14
by zguven
I send to you sample test project, sql code is below.
Code: Select all
create table TESTTABLE
(
ID NUMBER not null,
TEST1 VARCHAR2(10),
TEST2 VARCHAR2(10),
TESTFIELD VARCHAR2(25)
);
alter table TESTTABLE
add constraint PK_TESTTABLE primary key (ID);
alter table TESTTABLE
add constraint UQ_TEST unique (TESTFIELD);
delete from TESTTABLE;
commit;
insert into TESTTABLE (ID, TEST1, TEST2, TESTFIELD)
values (1, 'test', 'wqe', '1');
insert into TESTTABLE (ID, TEST1, TEST2, TESTFIELD)
values (2, 'wqwqw', 'qwe', null);
insert into TESTTABLE (ID, TEST1, TEST2, TESTFIELD)
values (3, 'wqe', 'wq', '2');
insert into TESTTABLE (ID, TEST1, TEST2, TESTFIELD)
values (4, 'qwe', 'qw', null);
insert into TESTTABLE (ID, TEST1, TEST2, TESTFIELD)
values (5, 'wqe', 'we', '3');
insert into TESTTABLE (ID, TEST1, TEST2, TESTFIELD)
values (6, 'wqe', 'qw', null);
insert into TESTTABLE (ID, TEST1, TEST2, TESTFIELD)
values (7, 'wqe', 'eqw', '4');
insert into TESTTABLE (ID, TEST1, TEST2, TESTFIELD)
values (8, 'qwe', 'wq', null);
commit;
Posted: Tue 06 May 2008 14:16
by Alexey.mdr
OraDirect .NET follows standard ADO.NET architecture and raises such exception.
Standard Microsoft data provider for Oracle also raises an same exception.
You should either insert unique data or not enforce a constraint.
Posted: Tue 06 May 2008 15:52
by zguven
Alexey.mdr wrote:OraDirect .NET follows standard ADO.NET architecture and raises such exception.
Standard Microsoft data provider for Oracle also raises an same exception.
You should either insert unique data or not enforce a constraint.
I want to solve this problem. any way to disable this constraint.
Oracle running without exception, but driver not running
Posted: Tue 06 May 2008 17:41
by zguven
I remove constraint from Constraints property in the "Properties window". but its working properly only "Preview..." window.
Posted: Wed 07 May 2008 10:27
by Alexey.mdr
To solve the problem try setting IsUnique sub-property to false
in the Columns property of oracleDataTable1.
Hope it helps!
Posted: Wed 07 May 2008 12:54
by zguven
Thanks its work!
Posted: Thu 08 May 2008 09:28
by Alexey.mdr
That's great!
Feel free to contact us if you have any problems or concerns about the product.