I am working with Oracle 11g and I got a question.
What I want to do is :
make a procedure
when this procedure has called, it will move data form one table to the other (column is almost same, but has different primary key)
Since, they do not use same field as PK, it occurs an error if use insert statement only.
So I want to do if table has a key than update, otherwise insert.
i.e. DDL like follow. It has almost same, but pk.
create table Tbl_A (
a_pk number constraints pk_tbl_a primary key
, b_pk number
, some_text varchar2(10)
, created date
, changed date
);
create table Tbl_B (
a_pk number
, b_pk number constraints pk_tbl_b primary key
, some_text varchar2(10)
, created date
, changed date
);
Psuedo of what I want :
create or replace procedure mv_data
is
begin
case when [if Tbl_B has same b_pk] then [update statement] end
else [create statement] end;
commit;
end;
I know I can not use case when like above, but that what I am trying to achieve is something like that. MyBatis could be a solution, but the client want to this with only DB.(Actually, this job will be executed by Oracle DBMS_SCHEDULE)
Thanks for your kind answers :D
As an alternative to the MERGE solution as suggested by valentin you can use the following construction:
begin
-- try the insert
insert...
exception
when dup_val_on_index
then
update...
end;
You want to use MERGE
Some references:
https://oracle-base.com/articles/9i/merge-statement
http://psoug.org/reference/merge.html
Related
I would receive an error:
ORA-02437: cannot validate (%s.%s) - primary key violated
Cause: attempted to validate a primary key with duplicate values or null values
I found it was because I have a stored procedure that increments the ID, but it had failed to do so when it re-ran and had an error related to one of my datatypes. I found I now had a duplicate ID in my database table. All this made sense and I was able to easily rectify it with a DELETE FROM MyTable WHERE ID = x, where x was the offending duplicate ID. The problem I have is the only way I was able to even find the IDs that were duplicated is in the first place is because I did a SELECT * FROM MyTable WHERE ID = x -- where x was one greater than the last ID I could actually see. I found it just by an educated guess. So:
Why can't I see these duplicate IDs when I open the table in Oracle SQL Developer? It only shows the last row as the ID before the duplicates. I don't think it is because of my primary key constraint, since the first line in my stored procedure is to remove that (and put it back, at the end - probably when I got my error), and it was not present when I looked at my table.
Is there some way to make these last IDs that got inserted into the table visible, so I wouldn't have to guess or assume that the duplicate IDs are "hiding" as one greater than the last ID I have in my table, in the future? There is a commit; in my stored procedure, so they should have appeared -- unless, of course, the procedure got hung up before it could run that line of code (highly probable).
Stored procedure that runs:
create or replace
PROCEDURE PRC_MYTABLE_INTAKE(
, EMPLOYEE_ID IN NVARCHAR2
, TITLE_POSITION IN NVARCHAR2
, CREATED_DATE IN DATE
, LAST_MODIFIED IN DATE
) AS
myid integer := 0;
appid integer := 0;
BEGIN
-- disable PK constraint so it can be updated
EXECUTE IMMEDIATE 'ALTER TABLE MYTABLE DROP CONSTRAINT MYTABLE_PK';
COMMIT;
-- assign ID to myid
SELECT ID INTO myid FROM MYTABLE WHERE ROWID IN (SELECT MAX(ROWID) FROM MYTABLE);
-- increment
myid := myid + 1;
-- assign APPLICATION_ID to appid
SELECT APPLICATION_ID INTO appid FROM MYTABLE WHERE ROWID IN (SELECT MAX(ROWID) FROM MYTABLE);
-- increment
appid := appid + 1;
-- use these ids to insert with
INSERT INTO MYTABLE (ID, APPLICATION_ID,
, EMPLOYEE_ID
, TITLE_POSITION
, CREATED_DATE
, LAST_MODIFIED
) VALUES(myid, appid,
, EMPLOYEE_ID
, TITLE_POSITION
, CREATED_DATE
, LAST_MODIFIED
);
COMMIT;
-- re-enable the PK constraint
EXECUTE IMMEDIATE 'ALTER TABLE PASS ADD CONSTRAINT MYTABLE_PK PRIMARY KEY (ID)';
COMMIT;
END;
Here's one problem:
SELECT ID
INTO myid
FROM MYTABLE
WHERE ROWID IN (SELECT MAX(ROWID) FROM MYTABLE)
There is no correlation between ID and ROWID, so you're not getting the maximum current ID, you're just getting the one that happens to be on the row that is furthest from the start of a datafile with a high number.
The code you need is:
SELECT COALESCE(MAX(ID),0)
FROM MYTABLE;
Or better yet, just use a sequence.
No idea why you're dropping the PK either.
Furthermore, when you issue the query:
SELECT APPLICATION_ID INTO appid ...
... that could be for a different row than the one you already got the id for, because a change could have been committed to the table.
Of course another issue is that you can't run two instances of this procedure at the same time either.
For David Aldridge, since he wants to look at code instead of the real reason I posted my question, run this ---
CREATE TABLE YOURSCHEMA.TESTING
(
TEST_ID NVARCHAR2(100) NOT NULL
, TEST_TYPE NVARCHAR2(100) NOT NULL
, CONSTRAINT TEST_PK PRIMARY KEY
(
TEST_ID
)
ENABLE
);
create or replace
PROCEDURE PRC_TESTING_INSERT(
TEST_TYPE IN NVARCHAR2
) AS
testid integer := 0;
BEGIN
-- disable PK constraint so it can be updated
EXECUTE IMMEDIATE 'ALTER TABLE TESTING DROP CONSTRAINT TEST_PK';
COMMIT;
-- assign TEST_ID to testid
SELECT TEST_ID INTO testid FROM TESTING WHERE ROWID IN (SELECT MAX(ROWID) FROM TESTING);
-- increment
testid := testid + 1;
-- use this id to insert with
INSERT INTO TESTING (TEST_ID, TEST_TYPE) VALUES(testid, TEST_TYPE);
COMMIT;
-- re-enable the PK constraint
EXECUTE IMMEDIATE 'ALTER TABLE TESTING ADD CONSTRAINT TEST_PK PRIMARY KEY (TEST_ID)';
COMMIT;
END;
SET serveroutput on;
DECLARE
test_type varchar(100);
BEGIN
test_type := 'dude';
YOURSCHEMA.PRC_TESTING_INSERT(test_type);
-- to verify the variable got set and procedure ran, could do:
--dbms_output.enable;
--dbms_output.put_line(test_type);
END;
Now, because there is no data in the table, the stored procedure will fail with ORA-06512: no data found. If you then try and run it again, you will get ORA-02443: cannot drop constraint - nonexistent constraint, because the EXECUTE IMMEDIATE 'ALTER TABLE TESTING DROP CONSTRAINT TEST_PK'; successfully dropped it, and the procedure never ran the command at the end to re-add it. This is what made me think I needed the commits, but even without them, it still will not complete the whole procedure.
To prove that the procedure DOES run, if given proper data, run this after creating the table, but before creating/running the stored procedure:
INSERT INTO TESTING (TEST_ID, TEST_TYPE)
VALUES ('1', 'hi');
And if you run the proc from a new table (not one with its constraint dropped), it will run fine.
Since mathguy didn't post this as the answer, though I'll credit him for the information...
Answer to why I can't see the duplicates is because the COMMIT does not occur in the procedure when it failed due to a datatype mismatch (which we found was actually in the application's code that sent the variable's values into this procedure, not in the stored procedure, itself). (It's also why I'll mark down anyone that says you don't have to add so many COMMIT lines in this procedure.) The commands were run in the session of the user that starts it - in my case, another session of the same DB user I was logged in with, but started from my application, instead of my SQL Developer session. It also explains why I could do a COMMIT, myself, but it did not affect the application's session - I could not commit any actions ran from another session. Had I ran a COMMIT as an OracleCommand and did an .ExecuteNonQuery on my OracleConnection right after the failure within the catch of my application, I would have seen the rows in SQL Developer without having to do a special query.
So, in short, the only way to see the items was with a direct query using WHERE ID =, find the last ID and increment it, and put it in the query.
Procedure is to check the the eid ,and do merge. While updating the existing row, it needs to update with the eid.seq.nextval.
I have created a the sequence and calling in Procedure.
CREATE OR REPLACE PROCEDURE Temp(
Eid Number,
dpt varchar2
) As
BEGIN
MERGE INTO Src1 e
USING (select v_eid as eid
, v_dept as dept
FROM dual) d
ON (e.eid = d.eid)
WHEN NOT MATCHED THEN
INSERT (e.eid,e.dept)
VALUES(d.eid, d.dept)
WHEN MATCHED THEN
UPDATE SET e.eid = eid_SEQ.nextval, e.dept = d.dept;
END;
/
Error:
1.ORA--38104:ORA-38104: Columns referenced in the ON Clause cannot be updated.
IF I remove the ON clause condition then PK cannot be null error .
Also, the best procedure to call the seq.nextval in the procedure.
Any help is greatly appreciated!
What you want to do is impossible with a merge statement. Think about it: you're trying to update the value of a field that is used to determine if the field should be updated. This is not safe, especially if the merge statement updates/inserts more than one row.
Apart from that it is close to impossible to suggest an alternative since eid seems to be a primary key and updating primary keys is normally a bad thing.
I'm recieving the ORA-01403 no data found error when trying to insert in a table after creating the following trigger:
CREATE OR REPLACE TRIGGER unic_disc
BEFORE insert ON disciplina
FOR EACH ROW
DECLARE
CURSOR cursor_professor IS
SELECT matricula_professor
FROM disciplina;
temp_prof disciplina.matricula_professor%type;
BEGIN
OPEN cursor_professor;
FETCH cursor_professor INTO temp_prof;
CLOSE cursor_professor;
END;
/
(the variables are in portugues, but their name does not interfere in the logic.)
the table creation,
CREATE TABLE disciplina (
codigo_disciplina NUMBER,
ementa VARCHAR2(50) NOT NULL,
conteudo_programatico VARCHAR2(100) NOT NULL,
matricula_professor NUMBER NOT NULL,
CONSTRAINT disciplina_pk PRIMARY KEY (codigo_disciplina),
CONSTRAINT disciplina_matricula_prof_fk FOREIGN KEY (matricula_professor) REFERENCES professor (matricula_professor)
);
My insert query:
INSERT INTO disciplina (codigo_disciplina,ementa,conteudo_programatico,matricula_professor) VALUES (7,'E6', 'C6',7777);
EDIT: I think the error is because I am selecting from the same table I'm editing.
I just needed to add PRAGMA_AUTONOMOUS_TRANSACTION after the DECLARE AND IT WORKED. I couldn't find it on my own, a friend told me.
Yes you are using a trigger (before insert) initially the table does not have any data and
the trigger is fired before insert when you are trying to insert data in the table, it
returns you with no records found . if you specify what is your requirement exactly i will
try to help you with the code .
I am having problems with this code below, which is a trigger used in Oracle SQL:
CREATE OR REPLACE TRIGGER TRG_TUTOR_BLOCK
BEFORE INSERT OR UPDATE ON tutors
FOR EACH ROW
DECLARE
BEGIN
IF :new.tutorName = :old.tutorName
THEN
RAISE_APPLICATION_ERROR(-20101, 'A tutor with the same name currently exists.');
ROLLBACK;
END IF;
END;
/
This trigger is used to prevent users from entering the same tutor name at different records.
After I insert two records with the same tutorname, the trigger does not block me from inserting it. Is there anyone can tell me what are the problems with this coding? Here are the sample format and insert values:
INSERT INTO tutors VALUES (tutorID, tutorName tutorPhone, tutorAddress, tutorRoom, loginID);
INSERT INTO tutors VALUES ('13SAS01273', 'Tian Wei Hao', '019-8611123','No91, Jalan Wangsa Mega 2, 53100 KL', 'A302', 'TianWH');
Trigger in Kamil's example will throw ORA-04091, you can see this with your own eyes here. ROLLBACK in a trigger is unnecessary, it runs implicitly when a trigger makes a statement to fail.
You can prohibit any DML on table by altering it with read only clause:
alter table tutors read only;
At last, integrity should be declarated with integrity constraints and not with triggers.
Good luck!
You don't need a trigger for this in Oracle.
You can do it with an "unique index" on the tutorName column (see http://docs.oracle.com/cd/B28359_01/server.111/b28310/indexes003.htm#i1106547).
Note: about your trigger, it fails on checking for another record with the same tutorName because it's not scanning the tutors table for another record with the same tutorName, it's just comparing the tutorName values of the row you are creating (in this case, old.tutorName is just NULL, because the row doesn't exist yet).
Check the case in yours trigger body
IF :new.tutorName = :old.tutorName
It returns true only if 'tutorName' value is the same in new and old record. When you'll trying to updat some value you'll get
IF 'someTutorName' = 'someTutorName'
which will return TRUE.
Inserting row cannot fire this rule because you're trying to compare something like that:
'someTutorName' = NULL
This case always returns FALSE.
Try to use something like that
CREATE OR REPLACE TRIGGER TRG_TUTOR_BLOCK
BEFORE INSERT OR UPDATE ON tutors
FOR EACH ROW
DECLARE
rowsCount INTEGER;
BEGIN
SELECT COUNT(*) FROM tutors WHERE tutorName is :new.tutorName INTO rowsCount;
IF rowsCount > 0
THEN
RAISE_APPLICATION_ERROR(-20101, 'A tutor with the same name currently exists.');
ROLLBACK;
END IF;
END;
/
But the best solution is the one mentioned by friol - use unique index by executing SQL like this
ALTER TABLE tutors
ADD CONSTRAINT UNIQUE_TUTOR_NAME UNIQUE (tutorName);
If you wanna completely ignore recording a row to a table you can follow these steps
rename table to something else and create a view with the same name and create an instead of trigger.
create table usermessages (id number(10) not null)
GO
alter table usermessages rename to xusermessages
GO
create or replace view usermessages as (select * from xusermessages)
GO
create or replace trigger usermessages_instead_of_trg
instead of insert or update on usermessages
for each row
begin
Null ;
end ;
GO
insert into usermessages(123)
Live test available here below
http://sqlfiddle.com/#!4/ad6bc/2
I want to have an 'updateinfo' table in order to record every update/insert/delete operations on another table.
In oracle I've written this:
CREATE TABLE updateinfo ( rnumber NUMBER(10), tablename VARCHAR2(100 BYTE), action VARCHAR2(100 BYTE), UPDATE_DATE date )
DROP TRIGGER TRI_TABLE;
CREATE OR REPLACE TRIGGER TRI_TABLE
AFTER DELETE OR INSERT OR UPDATE
ON demo
REFERENCING NEW AS NEW OLD AS OLD
FOR EACH ROW
BEGIN
if inserting then
insert into updateinfo(rnumber,tablename,action,update_date ) values(rownum,'demo', 'insert',sysdate);
elsif updating then
insert into updateinfo(rnumber,tablename,action,update_date ) values(rownum,'demo', 'update',sysdate);
elsif deleting then
insert into updateinfo(rnumber,tablename,action,update_date ) values(rownum,'demo', 'delete',sysdate);
end if;
-- EXCEPTION
-- WHEN OTHERS THEN
-- Consider logging the error and then re-raise
-- RAISE;
END TRI_TABLE;
but when checking updateinfo, all rnumber column is zero.
is there anyway to retrieve the correct row number?
The only option is to use primary key column of your "demo" table.
ROWNUM is not what you are looking for, read the explanation.
ROWID looks like a solution, but in fact it isn't, because it shouldn't be stored for a later use.
ROWNUM is not what you think it is. ROWNUM is a counter that has only a meaning within the context of one execution of a statement (i.e. the first resulting row always has rownum=1 etc.). I guess you are looking for ROWID, which identifies a row.