I read a lot about it but didn't found any help on that.
My Situation:
I've two database tables which belongs together. This tables I want to query with EntityFramework. Because Table B contains for EntityFramework the discriminator (for choosing the correct class for Table A) I've created a View which Joins Table A and Table B.
This join is quite simple. But: I want also to store data with that View. The issue is, that EntityFramework also wants to store the discriminator. But this isn't possible because it would update/insert into two tables.
So I've tried to create an "Instead of" trigger to just update/insert Table A (because Table B doesn't matter and will never be updated).
When I created the trigger - everything fine. If I insert something with an SQL Statement - everything is fine. But: If I'm inserting directly in the View (using Oracle SQL Developer) it throws the Exception as below:
ORA-22816 (unsupported feature with RETURNING clause).
If I do the same with EntityFramework I get the same error. Can someone help me?
Below my Code:
Table A and Table B:
CREATE Table "TableA"
(
"ID" Number NOT NULL,
"OTHER_VALUESA" varchar2(255),
"TableB_ID" number not null,
CONSTRAINT PK_TableA PRIMARY KEY (ID)
);
CREATE Table "TableB"
(
"ID" Number NOT NULL,
"NAME" varchar2(255),
"DISCRIMINATOR" varchar2(255),
CONSTRAINT PK_TableB PRIMARY KEY (ID)
);
The Joined View:
Create or Replace View "JoinTableAandB"
(
"ID",
"OTHER_VALUESA",
"TableB_ID",
"DISCRIMINATOR"
) AS
select tableA.ID, tableA.OTHER_VALUESA, tableA.TableB_ID, tableB.DISCRIMINATOR
from TABLEA tableA
inner join TABLEB tableB on tableA.TableB_ID = tableB.ID;
And finally the Trigger:
create or replace TRIGGER "JoinTableAandB_TRG"
INSTEAD OF INSERT ON "JoinTableAandB"
FOR EACH ROW
BEGIN
insert into TABLEA(OTHER_VALUESA, TABLEB_ID)
values (:NEW.OTHER_VALUESA, :NEW.TABLEB_ID);
END;
I've also tried it (to verify if the insert is correct just to enter "NULL" into the trigger instead of insert. But got the same error message.
Does anybody know how to solve this? Or does anybody have a good alternative (better Idea)?
Thanks!
Note: I've also defined a sequence for TableA's ID so that it will be generated automatically.
// Edit:
I found a possible Solution for MS SQL:
https://stackoverflow.com/a/26897952/3598980
But I don't know how to translate this to Oracle... How can I return something from a trigger?
Note: I've also defined a sequence for TableA's ID so that it will be generated automatically.
In EF StoreGenerated keys in Oracle are incompatible with INSTEAD OF triggers. EF uses a RETURNING clause to output the store generated keys, which doesn't work with INSTEAD OF triggers.
Related
I have two instances of the same database, but data is only committed to the "original" one. I need to copy inserted data from certain tables and commit them to the same tables in the second DB automatically. How can I do it?
I've already created synonyms for the tables in the second DB on original and within a specially prepared trigger I tried to use INSERT INTO ... statement with :new. but it is causing the data to not be committed anywhere and I receive Oracle Errors like:
ORA-02291: integrity constraint (PRDBSHADOW.FK_ED_PHY_ENT) violated.
Here is my trigger code
create or replace TRIGGER INS_COPY_DATA
AFTER INSERT ON ORIGDB.TABLE_A
REFERENCING NEW AS NEW OLD AS OLD
FOR EACH ROW
BEGIN
insert into COPY_TABLE_A(val1,val2,val3,val4) values (:new.val1, :new.val2, :new.val3, :new.val4);
END;
I think the entry in parent table is missing here. At least the FK ending of constraint is telling me so.
It means you need to insert first all the data into a "parent" table in order to be able to insert records in a "child".
For example the table auto_maker is having 3 rows only: Audi, Peugeot, and Honda.
Another table named "model" has 2 columns "maker" and "model". "maker" is a foreign key referencing to the "auto_maker" table.
It means in the models table are only the records allowed whose "maker" column value exists in "auto_maker" table.
In other words only these are available:
maker model
Audi A4
Peugeot 308
Honda Accord
Of course you can enter every model you wish, but "maker" value has to exist in the auto_maker table.
This is what probably happen - the trigger tries to insert a data in a column which is referencing to a "parent" table and the :new value just doesn't exist.
The following script will let you know what table you need to fill first.
select aic.index_owner, aic.table_name, aic.column_name
from all_constraints uc,
all_ind_columns aic
where aic.INDEX_NAME = uc.r_constraint_name
and uc.table_name = 'TABLE_A'
and uc.constraint_type = 'R';
If the query returns something just create similar triggers on those tables with similar logic you already have
Please tell me how can I move dependencies (such as PK, FK and indexes) from one table to another within the same database in Oracle? The second table is a copy of the first, only created later for partition reasons. Thank you in advance! :)
You could look at using the dictionary views in oracle, specifically the USER_CONSTRAINTS view. Then either construct a SQL statement dynamically or use DBMS_METADATA.get_ddl procedure to get the ddl for the constraint. You could do a REPLACE on the SQL to replace the original table name and constraint name with a new constraint name and the name of the new table.
create table autos (
id integer generated by default on null as IDENTITY unique,
owner_name nvarchar2(50)
);
Then I insert in table several rows
insert into autos
(owner_name)
VALUES
('Nick');
insert into autos
(owner_name)
VALUES
('Tommy');
2 rows inserted, then for increase rows count, I run this query
insert into autos
(owner_name)
select owner_name
from autos;
Several query was run successfully, but after this, oracle returns error: ORA-30667: cannot drop NOT NULL constraint on a DEFAULT ON NULL column
Tell please, what is wrong here?
P.S. I use SQL Developer.
UPDATE
If I am trying all above codes in sys database connection, all works fine, but I am create new user (here is code how I create new user)
CREATE USER C##OTO_USER
IDENTIFIED BY oto_user_pass;
GRANT ALL PRIVILEGES TO C##OTO_USER;
Then I create new connection with C##OTO_USER and only in this connection happens above error.
Also, that error happens sometimes, sometimes INSERT query works fine.
And not only INSERT... SELECT, but usually INSERT statement also causes that error.
So, I think this is new user/connection problem, may be above user creating code, not creates complete user?
If trying inserting with SQL*PLUS, also same error happens.
Your problem is that when you use IDENTITY in the column definition, you should take into account its restrictions.
If you want to insert rows as subquery so you encounter with following restriction: CREATE TABLE AS SELECT will not inherit the identity property on a column (source). Same situation happens with your insert, IDENTITY unique doesnt work properly.
insert into autos
(owner_name)
select owner_name
from autos;
Something strange happened to me today ,my friends(developers) said its probably a bug ... Usually when I want to see the DDL of a table in PL/SQL , I right-click on the table and then I click on view and I get the DDL .However, there is another way I can get the DDL of a table and by right clicking on the table and there something called DBMS_METADATA then I put my cursor on it and it will show me DDL. In the image that I upload there a difference between the DBMS_METADATA and the 'view' .Number 1 represents the 'view' and the 2 represents the DBMS_METADATA, if you notice there is a huge difference between the two .The first one shows column organization_code its not null (because its not checked) but the 2nd one shows organization_code is null. this made the developers confused, which one they should count on ? .But after testing the column its not null. I should mention that is column is a primary key so it should be NOT null why in medata showed a wrongs information ? does that happened to anyone before ?(by the way i am using 11g)
A column used for a primary key cannot be null1. However, that restriction can be enforced solely through a primary key constraint, and does not require a separate not null constraint. The IDE, PL/SQL Developer, is showing you a generally more useful combination of primary key constraints and not null constraints. DBMS_METADATA is showing you exactly how the tables were specified, which is irrelevant unless you plan on dropping the primary keys.
create table table1(a number not null primary key);
create table table2(a number primary key);
begin
dbms_metadata.set_transform_param(dbms_metadata.session_transform,
'SEGMENT_ATTRIBUTES',false);
end;
/
select dbms_metadata.get_ddl('TABLE', 'TABLE1') from dual;
CREATE TABLE "JHELLER"."TABLE1"
( "A" NUMBER NOT NULL ENABLE,
PRIMARY KEY ("A") ENABLE
)
select dbms_metadata.get_ddl('TABLE', 'TABLE2') from dual;
CREATE TABLE "JHELLER"."TABLE2"
( "A" NUMBER,
PRIMARY KEY ("A") ENABLE
)
In PL/SQL Developer, neither column has Nullable checked.
1 Unless you use a novalidated non-unique index, which is extremely rare.
I'm trying to update some existing code that is supposed to write data to a variety of Databases (SQL, Access, Oracle) via ODBC, but I'm having a few problems with Oracle and am looking for any suggestions.
I've set my Oracle database up using a Trigger (basic tutorial online, which I'd like to support).
CREATE TABLE TABLE1 (
RECORDID NUMBER NOT NULL PRIMARY KEY,
ID VARCHAR(40) NULL,
COUNT NUMBER NULL
);
GO
CREATE SEQUENCE TABLE1_SEQ
GO
CREATE or REPLACE TRIGGER TABLE1_TRG
BEFORE INSERT ON TABLE1
FOR EACH ROW
WHEN (new.RECORDID IS NULL)
BEGIN
SELECT TABLE1_SEQ.nextval
INTO :new.RECORDID
FROM dual;
end;
GO
I then populate a DataTable using a SELECT * FROM TABLE1. The first problem is that this DataTable doesn't know that the RecordId column is auto-generated. If I have data in my table then I can't alter it because I get a error
Cannot change AutoIncrement of a DataColumn with type 'Double' once it
has data.
If I continue, ignoring this, then I quickly get stuck. If I create a new DataRow and try to insert it, I can't set RecordID to DBNull.Value because it complains that the column has to be non-null (NoNullAllowedException). I can't however generate a value myself, because I don't know what value I should be using really, and don't want to screw up the trigger by using the next available value.
Any suggestions on how I should insert data without ODBC complaining?
It does not appear that your first problem is with an Oracle database. There is no such thing as an "Autoincrement" column in Oracle. Are you sure that message is coming from an Oracle database?
With Oracle, you should be able to provide any dummy value on insert for the primary key, and the trigger will overwrite it.
There is also nothing in your provided description that would prevent you from updating this value in Oracle (since your trigger is on insert only) unless you have foreign key references to the key.