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:-
~~~~~~~~~~~
Instance 1 of A
-> Entity Bean -> Database (only 1 row exist)
Instance 2 of A
My Query is:-
1) In Approach A, both the instances of Application
have their own Entity Bean (running in same JVM as them,
packaged with Application)..Now both the entity bean instances
represent 1 row on Database...At one time only 1 Entity bean
will be performing the operation (read/write, other will be
disallowed).
2) In Approach B, both the instances of application(or Client) using
the same Entity Bean - which is representing 1 row of Database
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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Eric Temel

"Michael Jouravlev" <[email protected]> wrote in message
news:[email protected]..
>
"Eric Temel" <[email protected]> wrote in message
news:[email protected]..
Q3: Does the weblogic will ready all beans if client executehome.findByALL().
(findByAll method return all product), that will consume a lot of memoryif there
is a mass of client do that?WL has a setting which allows you to find a bean without loading it.Search
docs.
ah, good point. To be redundant, even though the beans are found and not
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to),
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Something to keep in mind if memory is an issue..
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Can any one please explain why we are using inheritance instead of creating object of base class????

SumitThokal wrote:
One very basic question about inheritance.
Why we need inheritance?
the benefit of inheritance also achieve by creating instance of base class using it in other class instead of extending the base class.
Can any one please explain why we are using inheritance instead of creating object of base class????What did you find out when you looked on Google?
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The behaviour changes according to these descriptor settings: concurrency-strategy,
db-is-shared and include-updates.
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