I have a insert statement on table "test". PK on column x in the table "test".
Now while inserting if duplicate row comes then the same row should get updated instead insert.
How can i achieve this.
Is it possible by dup_val_on_index?
Please help.
First create a copy of the above table without any KEY Columns and follow
Step 1: truncate the table first whenever you encounter a bunch of insert statement comes
Step 2: INSERT the above truncated tables
Step 3: Execute the MERGE statement like below
MERGE INTO TABLE_MAIN M
USING TABLE_MAIN_COPY C
ON (m.id = c.id)
WHEN MATCHED THEN UPDATE SET M.somecol = c.somecol
WHEN NOT MATCHED THEN INSERT (m.id, m.somecol)
VALUES (c.id, c.somecol);
You may incur error while on merger ORA-30926: unable to get a stable set of rows in the source tables when there is two or more rows while on update.
you may avoid that using the GROUP function related to id or like ORA-30926: unable to get a stable set of rows in the source tables
Related
I need to add a new row in existing table using Oracle plsql.which doesn't have unique identity column. For example table contain id_no,name of 40 rows.i need to add 40 more rows in same table. I want to add next continues number of max(id_no). For name I am going to insert it manually.without using auto increment.
Try an insert statement with subquery select max(id_no)+1 from table.
I want to insert a one or more records in table A.
But same record already existing in records with status Active
CREATE PROCEDURE Test
AS
BEGIN
INSERT INTO A (x,y,z,status)
SELECT data FROM A WHERE some condtion;
... Here i want to update table A status column into 'N', if the inserted data already existing in table A Compared with x,y,z column.
EXCETION
---Handled
END;
You can try this:
MERGE INTO target_table t
USING source_table s
ON (t.id = s.id)
WHEN MATCHED THEN
UPDATE SET t.col1 = s.col1
WHEN NOT MATCHED THEN
INSERT (col1, col2) VALUES (s.col1, s.col2);
Documentation Link: https://docs.oracle.com/cd/B28359_01/server.111/b28286/statements_9016.htm#SQLRF01606
What you probably want to do is a merge-statement. The merge statement checks if the dataset already exists. In this case you can formulate an update statement. For example, you could update the status. If not, the new dataset will be inserted.
For further information you should hava a look here.
The merge is the way to go. Another approach is first updating all the rows that match the criteria and after do the insert.
However, if your problem is how to differentiate the 2 rows, use the pseudo-column ROWID.
I know that ROWID is distinct for each row in different tables.But,I am seeing somewhere that two tables are being merged using rowid.So,I also tried to see it,but I am getting the blank output.
I have person table which looks as:
scrowid is the column which contains rowid as:
alter table ot.person
add scrowid VARCHAR2(200) PRIMARY KEY;
I populated this person table as:
insert into ot.person(id,name,age,scrowid)
select id,name, age,a.rowid from ot.per a;
After this I also created another table ot.temp_person by same steps.Both table has same table structure and datatypes.So, i wanted to see them using inner join and I tried them as:
select * from ot.person p inner join ot.temp_person tp ON p.scrowid=tp.scrowid
I got my output as empty table:
Is there is any possible way I can merge two tables using rowid? Or I have forgotten some steps?If there is any way to join these two tables using rowid then suggest me.
Define scrowid as datatype ROWID or UROWID then it may work.
However, in general the ROWID may change at any time unless you lock the record, so it would be a poor key to join your tables.
I think perhaps you misunderstood the merging of two tables via rowid, unless what you actually saw was a Union, Cross Join, or Full Outer Join. Any attempt to match rowid, requardless of you define it, doomed to fail. This results from it being an internal definition. Rowid in not just a data type it is an internal structure (That is an older version of description but Oracle doesn't link documentation versions.) Those fields are basically:
- The data object number of the object
- The data block in the datafile in which the row resides
- The position of the row in the data block (first row is 0)
- The datafile in which the row resides (first file is 1). The file
number is relative to the tablespace.
So while it's possible for different tables to have the same rowid, it would be exteremly unlikely. Thus making an inner join on them always return null.
I am using an AFTER INSERT row trigger in Oracle 11g to copy specific columns from one table to another on insert. I have the trigger and insert working ok. The problem I have is that I need to insert the new data from one column to a different column when copying it.
The trigger info reads:
BEGIN
insert into BALES_STORAGE
(CROP,
CUTTING,
DESTINATION,
BALES_MOVED,
DATE_MOVED,
PASTURE,
TARGET_LB_PER_DAY)
values
(:new.CROP,
:new.CUTTING,
:new.MOVING_LOCATION,
:new.BALES_MOVED,
:new.DATE_MOVED,
:new.PASTURE,
:new.TARGET_LB_PER_DAY);
END;
The first table is called "BALES_HARVESTED" and the 2nd table the trigger inserts the selected columns into is called "BALES_STORAGE". I need to insert the :new.MOVING_LOCATION data into the column called DESTINATION on the second table.
So my question is: when using an after insert row trigger, how to I change the column that the data is inserted into?
Thanks for any help.
Matthew
Your trigger code worked just fine for me. Not sure what the problem is. The 3rd column in your INSERT statement does the column mapping correctly.
http://sqlfiddle.com/#!4/2d2fd5/1/1
Maybe you have different structures or foreign key constraints. Could you elaborate on what error you get? Does it produce an ORA- error? or does it simply not produce the desired result, but no error?
Trying to find a way to write an Oracle trigger that would check before an insert to see if a match was found in the primary column and if so update the row information instead of inserting a new row.
I've looked at before insert. Is there a way to cancel the insert based on criteria inside that block?
I've also looked at using the instead of clause but it requires working on a view.
What is the best way to go about this?
Use a MERGE statement instead of an INSERT.
Use a merge statement.
MERGE INTO <<your table>> t
USING (<<your list of records - can be the result of a SELECT >>)
ON ( <<join between table and list of records >>)
WHEN MATCHED THEN
UPDATE SET << the rows you want to set>>
WHEN NOT MATCHED THEN
INSERT (<<columns of table>>)
VALUES (<<value>>)
https://oracle-base.com/articles/9i/merge-statement