How does oracle work

can some one guide me or provide a link or document in detail about oracle like how it works....like what happens in undo segment..how it is used....kindly help me out...in short i would like to know fundamentals of how oracle works...

Concepts manual:
http://download.oracle.com/docs/cd/B19306_01/server.102/b14220/toc.htm

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How does oracle know which AO Framework page or process to execute.

Hi,
How does oracle know which AO Framework page or process to execute. I use to think this was defined in the Function definition. But looking through some Function definition in HRMS setup I noticed some of them simply calling the same first page, such as the one below used in many managers menus. This initial page is the page that allows managers to choose the employee they want to work on.
OA.jsp?akRegionCode=HR_PERSON_TREE_TOP_SS&akRegionApplicationId=800.
My question is, after executing this initial page, how does Oracle then varies the OA page by the diffferent functions?

Hi;
Thanks for sharing
Please dont forget to change thread status to answered if it possible when u belive your thread has been answered, it pretend to lose time of other forums user while they are searching open question which is not answered,thanks for understanding*
Regard
Helios

ORACLETEXTSEARCH - How Does it work?

Hi experts,
I had a many disccusions with my coleagues about ORACLETEXTSEARCH in the UCM11g. We found that we don't undestrand How does it work.
I have a basic questions:
1. Does ORACLETEXTSEARCH use only database engine for the indexing?
2. Can I start fulltext indexing without Oracle UCM? Only by database.
3. Are some differences between UCM10g and 11g?
Thank you for the answers and the explanation.
Martin

1. Oracle text is a DB tool installed at the DB level, however as others say the triggers to kick it off are done by UCM not independently at the DB. I do not think it could work that way.
2. No, but other indexing options are available like SES
3. 10g required a component to be added to the UCM server and required an 11.1.0.7.0 or greater oracle DB. 11g requires no extra component but still has the db requirement.
SES can be configured to index multiple different repositories (including UCM) and you can control the index rebuilds directly from SES as an option for number 2.

How Does MINUS Work?

Hi,
I want to do a count(*) table 1 minus count(*) table 2 in a test case. How does minus work in functions?
create table count1( col1 number);
create table count2( col2 number);
truncate table count1;
truncate table count2;
insert into count1 values(1);
insert into count1 values(2);
insert into count1 values(3);
insert into count1 values(4);
insert into count1 values(5);
commit;
insert into count2 values(1);
insert into count2 values(2);
insert into count2 values(3);
insert into count2 values(5);
commit;
SQL> select * from count1
2 minus
3 select * from count2;
      COL1
         4
SQL>
SQL> select count(*) from count1
2 minus
3 select count(*) from count2;
COUNT(*)
         5
SQL>

select * from count1
minus
select * from count2;Means all rows of count1 not present in count2, that is to say one row (4).
select count(*) from count1
minus
select count(*) from count2;Means number of rows of count1 if it is different from number of rows of count2, no rows if count1 and count2 contains the same number of rows
select count(*) from (
select * from count1
minus
select * from count2
);Means number of DISTINCT rows of count1 that are not present in count2
select count(a.rowid) - count(b.rowid)
from count1 a full outer join count2 b on a.rowid=b.rowid;Means number of rows of count1 - number of rows of count2, where - is arithmetic minus (not minus as defined in set theory).
Try inserting some duplicate values and you'll get it.
Max
[My Italian Oracle blog|http://oracleitalia.wordpress.com/2010/01/02/query-gerarchiche/]

How does Oracle client communicate with a database server

Looking to idenify how Oracle Database Client for OpenVMS communicates with database server and whether the protocol used is secure. Realize that it is using whatever the configured network protocol is (ie. tcpip) but is languauge it uses ( ie. SQL, etc..) secured/encrypted and if not what steps can be taken to encypt

Arizuddin wrote:
I have installed oracle client 10g on client pc for getting connection to Oracle databse 10g (runng on windows server) usng ODBC through SAGE ACC PAC (ERP). Working fine earlier. Now all of a suddent user starts complaining about database connection. When checked his pc registry values. Two values of ODBC keys are reset to null. Those are DSN and DRIVER values. How come this values reset to null? What is causing this to reset?Nothing in this has anything to do with the sever. You need to check what the client did on his machine that caused registry to get modified?
How does oracle ODBC works with Oracle database? Need to know all the steps involved?The connectoin from any client is initiated by a client process. This client process is supposed to get a server process to do his work. So if this is done, the client can work now with oracle . Please see the concepts guide for the gory details of the entire process.
HTH
Aman....

BPEL Engine: How does it work?

"[BPEL].. Engines will come in a variety of form factors and use different techniques for runtime representation of processes, including:
* interpretative
* code generation
* Obj Oriented models of Activities
* reduction engine based on Pi-Calcolus and related concepts"
[P. Brown& M. Szefler]
How does it work Oracle version of BPEL Engine exactly? Does it make a package (.jar) of Java classes and process them like usual Web Applications?

It is based on a mix of the first 3 techniques. The code gene part is really internal and is more about just in time compilation and performance optimization than generation of a Java application. -Edwin

How does oracle execute a correlated subquery .... some confusion

How does oracle 10g execute a correlated subquery?
I read some articles online & i am a little confused.
example:
select * from emp e
where e.deptno in (select d.deptno from dept d
where e.deptno = d.deptno);
My questions .......
1.In the above example, does oracle read the entire outer table first and then run the inner query using the rows returned by the outer query?
I read in some articles that they execute simultaneously.
How does this work?
2.Should the inner query have lesser amount of rows compared to the outer query for a good performance?
3.Can every correlated subquery be converted to a join and if so which one to use?
Truly appreciate any inputs on how oracle executes it at the backend.
Thanks in advance.

user10541890 wrote:
How does oracle 10g execute a correlated subquery?
I read some articles online & i am a little confused.
example:
select * from emp e
where e.deptno in (select d.deptno from dept d
where e.deptno = d.deptno);
My questions .......
1.In the above example, does oracle read the entire outer table first and then run the inner query using the rows returned by the outer query?
I read in some articles that they execute simultaneously.
How does this work?SQL is not a procedural language. SQL code specifies what the system sill do, not how the system wlll do it; that's entirely up to the system.
What does it matter to you whether the two are done together, or if one is completed before the other begins?
The system will probably choose to run ucorellated subqueiris only once, and correlated queries multiple times as needed.
2.Should the inner query have lesser amount of rows compared to the outer query for a good performance?That usually doesn't matter.
It some cases, you may want to consider whether the subquery is correlated or not. If the subquery is very costly, and produces, say, 1 million rows, but you know the main query will only produce about 5 rows, then you may want to do a correlated subquery rather than an uncorrelated one.
3.Can every correlated subquery be converted to a join and if so which one to use?I believe so.
Use whichever is easier to code and debug. That will change depnding on the data and the requirements.
If performance is an issue, try different ways. Usually, where I've noticed a big difference, join was fastest.
By the way, it's unusual to have a correlated IN-subquery.
Usually IN-subqueris are uncorrelated, like this:
select *
from      emp     e
where     e.deptno     in ( select d.deptno
                    from    dept     d
                  );(This and the queries below produce the same resutls as your original query.)
Correlated subqueries are usually used for scalar subqueries or EXISTS subqueries, like this:
select *
from      emp     e
where     EXISTS ( select d.deptno
           from    dept     d
                where   e.deptno = d.deptno
            );To do the same thing with a join:
select e.*
from      emp     e
join     dept     d     on     e.deptno     = d.deptno
;assuming dept.deptno is unique.

How does this work?

This is not a complaint, but a confused sigh of admiration. I've got an email account at the university where I teach. When I got my iBook, it took me a while, and a few conversations with IT at the school, to get this account working in the Mail application. (Since I have a Verizon DSL at home, I had to include that SMTP as the outgoing server.) Anyway, I synched this mail account (along with my AOL and .Mac accounts) onto the iPhone, and it works perfectly, both incoming and outgoing. I didn't have to change any of the settings. I thought I was computer savvy, but I can't wrap my mind around this. It seems like magic. How does it work?

The sync process with iTunes transfers the email account settings (for your chosen accounts via your iPhone sync preferences) from the Mail application on your Mac to the iPhone's email application.
The iPhone is running OS X and the iPhone's email client can be considered a mobile version of the Mail application.

My iPhone was stolen and I have contacted the police who are using the meid number to locate. How does this work and what are my chances of getting the phone back?

My iPhone was stolen. I used Find My iPhone app to lock it and display a message. The phone has not connected to the internet to locate it. I contacted the police and they have taken my meid number. How does this work and what are my chances of getting the phone back? Are there other ways the theif can use it. I was told once they put in a new sim card and use it, whatever software the police have, it will show up.

Honestly? In the US (I can't speak to other countries, though I doubt it works much differently in a lot of the world) The police took your report and filed it either in their computers or, on paper. They will now not think of this again. The only time it will cross anyones mind is if, in the course of entering information into evidence about items recovered or seized at a crime scene, the serial number of an iPhone that was found/seized happens to match yours, in which case you will be contacted.
The police in the US can and will do nothing to 'blok' the phone and it's not worth their time to try and locate it unless you know for a fact that it was stolen by a big time drug lord, master criminal, or some other such prime target and they can get a court order to track the location of the phone in order to locate this individual for your own purposes. If they do that, they'll probably keep him under surveilance for a year or so before they act.
Basically, the police don't care about your phone. If they find it, they will give it back to you. They are not, however, going to go looking for it. They have better things to do.
I'm sorry, but that's the way it is.

Was told a USB device would create a PDF automatically from the data contained within when plugged into my USB port. Doesn't seem to work. How does this work and how can I fix the device I received?

Acrobat is not on the USB device - only Adobe Reader needed on the PC. How does this work? How can I fix this device if at all?

You need to ask the people who sold it to you. Doesn't sound like it has anything to do with Reader.
However, you should be wary of devices that automatically try to open files when plugged in. They can also infect your computers with all kinds of viruses or malware.

HT2357 So how does this work on Mountain Lion? I cannot seem to ignore the iTunes 11 updates, which now seem to appear every 5 minutes!!

So how does this work on Mountain Lion? I cannot seem to ignore the iTunes 11 updates, which now seem to appear every 5 minutes!!

Fantastic! Didn't work at first so restarted App store and tried again. This time it asked 'ignore update'. All gone!

TS1425 My co worker has given me his iPod to take home and transfer his music to my laptop, however, I am unable to access his music to download it to my computer. How does this work?

My co-worker has given me his iPod to take home and transfer his music to my laptop, however, I am unable to access his music to download it to my computer. How does this work?

You need to transfer the iTunes Library from the most recent backup you made before the hard drive was replaced.
You can't transfer the full iTunes Library from the iPad back to iTunes.
There are third-party Windows applications that will transfer data from an iOS device, but they don't re-create the iTunes Library exactly as it was before.

How does Remote work with Apple TV?

How does Remote work with Apple TV?
1. Does Remote, "Play" the music that resides on your iPod Touch>Apple TV>Home Speakers.
OR
Does Remote "Control" the music that resides on Apple TV HD>Home Speakers.
(If so... say you have a iPod Touch that only holds 8GB's but your music collection on your Apple TV exceeds that amount.
Will Remote still "Control" the larger music collection on Apple TV or your computer?)
2. Will iPod Wifi work on a patio outside a home to control Apple TV inside the home?
thank you in advance, Tom

Remote is a way to control iTunes on either your computer or Apple TV using a WiFi connection. See this article for complete instructions.

I got a itunes gift card and when i try and buy some thing it asks me for my credit card details how does that work when i have £15 on my fone that i got on a gift card?

i got a itunes gift card and when i try and buy some thing it asks me for my credit card details how does that work when i have £15 on my fone that i got on a gift card? as i am trying to buy a song and it is starting to really cheese me of now where it keeps asking for credit card details is there a way round it with out having to use a credit card?

Contact iTunes Customer Service and request assistance
Use this Link > Apple Support iTunes Store Contact

I would like to know which app/software in MAC gives us the same feature that is provided by System Restore in Windows, and how does that work

I would like to know which app/software in MAC gives us the same feature that is provided by System Restore in Windows, and how does that work.

Time Machine is one such program, although it is a recursive backup program which offers limited archive capability, based on the capacity of the backup destination, and it requires you set it up before you start editing your files. Some programs are also Versions aware, which offers a kind of restore capability by file. Again needs to be setup before you start editing.
Just a for-your-info:
Mac is not an acronym, it is a nickname for Macintosh.

How does oracle work

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