Need help about entity bean relationshi

I have two entity bean,userBean(userid,username,password,email)and subscriptionBean(email,subtopic).so email column is FK,right?
but both email,subtopic fields in subscriptionBean are NOT set to be unique,i mean there should be many same email address with difference subtopic subscriptions.
so NO primaryKey in my second entity bean.is it OK?

Hello,
Your EJB MUST have a primary key !, so add a field ( maybe subscriptionId) to you bean which will be unique.
Regards,
Sebastien Degardin.

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Very Basic Question about Entity Beans !!! Need your help.

Hi,
I have the following requirement:-
==============================
There is an application A, whose multiple instances can run
at the same time. There is some data/variable which is to be
globally shared (i.e by all the instances). I have thought of using
Entity Beans and putting that data in a single record in DB.
Approach A:-
~~~~~~~~~~~
Instance 1 of A (with Entity Bean ) -
-> Database (only 1 row exist)
Instance 2 of A (with Entity Bean ) -
Approach B:-
~~~~~~~~~~~
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1) In Approach A, both the instances of Application
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2) In Approach B, both the instances of application(or Client) using
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Which is correct....I have read somewhere instance of Entity Bean
corresponds to 1 row of database....If that is the case, Approach
A would be wrong..
Please help.

1 Entity bean for 1 row is not true. An entity bean can represent data from multiple tables also. The correct statement is 1Entitybean for 1 resultset.
So in case 1, u have 2 instances of Application running so it should not be an issue.

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Disconnect the USB cable from the iPhone, but leave the other end of the cable connected to your computer's USB port.
Turn off the device: Press and hold the Sleep/Wake button for a few seconds until the red slider appears, then slide the slider. Wait for the device to turn off.If you cannot turn off the device using the slider, press and hold the Sleep/Wake and Home buttons at the same time. When the device turns off, release only the Sleep/Wake button.
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Questions about entity bean caching/pooling

We have a large J2ee app running on weblogic6.1 sp4. We are using entity beans
with cmp/cmr. We have about 200 EntityBeans and accessed quite heavily. We are
struggling with what is the right setting of max-beans-in-cache and idle-time-out.
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a. If a bean with primary key 100 exists in the cache, and the following
is done what is expected
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ii. findBySomeOtherKey(xyz)
which results in loading up bean with primary key 100
iii. cmr access to bean with
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Is the instance in the cache reused at all between transactions?
If there is minimal reuse of the beans in cache, Is it fair to assume that caching
can only help loading of beans within a transaction. If this is the case, is there
any driver to increase the max-beans-in-cache other than to avoid CacheFullException?
In other words, is it wrong to say that max-beans-in-cache should be set to the
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2. Again what is the driver of setting idle-time-out to a value? ( We currently
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The behaviour changes according to these descriptor settings: concurrency-strategy,
db-is-shared and include-updates.
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get the latest bean values. This overrides a true setting of delay-updates-until-end-of-tx.
The max-beans-in-cache setting refers to the maximum number of active beans (really
beans that have been returned by a finder in a txn that hasn't committed). This
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txn with a max-beans-in-cache of 3,000. Slow, but it works, showing 3,000 active
beans, and 27,000 passivated ones...).
This setting is checked in SP5, but I don't know about SP4. So you do need to
size appropriately.
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- The cache isn't nearly as useful as you'd like. You get far more db activity
with entity beans than you'd like (too many ejbLoads()). This is disappointing.
- findByPrimaryKey() finders can use the cache. How long the cache is kept around
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and optimistic locking. But I believe findByAnythingElse() finders still have
to hit the db - ejbql is never run against the cache, but is always converted
to SQL and run against the db.
Hope this is of some help - feel free to email me at simon-dot-spruzen-at-rbos-dot-com
(you get the idea!)
simon.

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872882 wrote:
Hi All,
Em..i just need some advice about choosing correct career path.I graduated with a first class in IT with business information science in 2009. In 2009 after looking for jobs for few months i took a manager post in a petrol station which i never wanted.(Due to the credit crunch & the Family financial reasons) .Then unfortunately i had to stay out of work for 18months due to a serious spinal code operation i had to face.now in 2011 July im fit & ready to start my life again. but im lost where to start/ which career path to choose. (i've still got the job at the petrol station as the manager)
ive liked data base management subject when i was in the University so, Ive been reading OCA-051 & interested on OCA qualification I just want to know what are the possible jobs i can apply if i get the certification? Basically what should i do to get any IT related job? :( ( i dont like programming)..
Please be kind to reply.
ps:i live in the Uk.
Thanks.You'll sit on your bum and ruin your back again with most IT jobs. With your government shrinking, OCA qualification won't have much worth unless you personally know someone in the private sector that needs help. An operator job with your petrol company (assuming it's not just a mom 'n pop station) would probably require heavy lifting.
IT is a good, solid, growing career path, but most of the work is still programming, and most ways up to better jobs go through that experience. You might be an exception if you have a way to join other skills with your IT education, such as business analysis or sales or web prettyfying. Perhaps the determinants are your personality and goals.
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Need help about entity bean relationshi

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