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Different ways of creating objects?

c4bef551-b678-4eed-950e-318f21a47a28Apr 29 2018 — edited Apr 30 2018

Hi All,

I am new to Java and am studying a text book on the subject.

I have come across the following two lines of code; each of which creates a new object -

Calendar cal = Calendar.getInstance();

Date now = new Date();

I have a reasonable understanding of the 'new' keyword, and it's relationship to creating objects.

However I am wondering if anybody can explain to me, or point me in the direction of a good resource, which thoroughly explains why some objects are created with dot(.) notation, e.g.: Calendar.getInstance();, and others are created with the 'new' keyword? I am anticipating that the difference will relate to 'System' classes, but I have no idea of what these actually are!

Any help here would be greatly appreciated.

Kind Regards,

Davo

Comments

Mike Kutz

It looks like table TEST1 is being used as a temp table.
In Forms, this should probably have been a GTT.
GTTs don't work in APEX dye to Connection Pooling. You'd use a Collection instead.
But, I'm just guessing about the purpose of TEST1.
(PS - you should probably have just done an INSERT... SELECT instead of parsing a cursor in a loop)

SANPAT

Dear Mike Kutz
I want to delete all the old records from test1. then i want to update the table with the latest Query data from test table. can you suggest how to insert the records using the procedure in Oracle Apex .
Delete all Data from A Table
Query on Table B and get the data
Insert the Query data into A Table.
Sanjay

Mike Kutz
Answer

APEX is stateless. It automatically calls COMMIT as needed (or ROLLBACK ).
I'd keep it simple, Sanjay (K.I.S.S.)

BEGIN
  DELETE FROM TEST1;

  INSERT INTO TEST1 (empno,name)
    SELECT empno, name FROM EMPLOYEE;
END;
Marked as Answer by SANPAT · Oct 17 2021
SANPAT

Dear Mike Kutz
Thanks , your given Query is perfectly runing on Sql Command, but the same Query when i update in the Form at server side condition , it's not working . it truncate the data but not updating with fresh data from the called table.
image.png
image.pngKindly sugget .
Sanjay

AndyH

As you are running this from a Dynamic Action it will be running in a different database session to that of your page. If your page hasn't committed it's data, the session in your DA will not see that data.
Is there a particular reason you are doing this work through a DA and not through a process?

SANPAT

Dear AndyH
I am new to Oracle Apex and Learning , Can you please give me some tips , how to take such query from Process.
Its getting executed properly , but i don't know how to display the message once the Procedure Query will update the table . Can you please suggest.
Sanjay

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Locked on May 28 2018
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