Need for persistence layer?

I don't know if this is the correct forum but this is my question:
Me and my colleague build a project that can be deployed on Oracle AS and Tomcat (struts DAO pattern). We have two database both are Oracle, one already exist and the other is a new Oracle DB(both are on different machines). We put db link on the two databases so we can have single queries on the tables of the 2 different DB. We also have web services for stored procedure calls. Now my question is do we need a persistence layer(e.g. Oracle Toplink, hibernate) to access the database object of the two different databases?

thanks fo the idea ram. im only just confused if i needed the mapping.. in this case DAO is enough.

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This should do it...
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Hi,
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Thanks
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Hi,
I have a swing application that needs to perfom a
great many database actions. I have currently
architected it such that I have a singleton class
that contains all of the methods and interact with
the DB via JDBC. I have always wondered if this is
the correct approach.
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JuckkyThis is a feasable approach, if the database is simple, you can just use JDBC directly, if it's more complex Hibernate is probably a good choice. The database singleton should act as a worker thread processing actions off a queue and posting back results using a listener. This way the GUI remains responsive even when the database gets blocked.
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Hi,
In SXMB_MONI there are messages with status "system error manual restart possible" and "scheduled". when i try opening those messages it says "XML message not found". I no longer need those messages and want to delete them. But when i try to cancel those messages it says " Error accessing persistence layer".
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Regards,
Mateen.

Hi Meetan
refer these thread for the same may be helpful for you
IS_Retry and RSXMB_RESTART_MESSAGES
release queue
BPM error
/people/krishna.moorthyp/blog/2005/11/28/inactive-integration-process-ip-at-run-time
Thanks!!

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1.
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While looking at it I can see that since a caller is searching for exactly 1 object then if the query finds more than one object then a UnexpectedMultipleBusinessObjectsFoundException could be thrown. But I don't believe an NotFoundException is warranted. What are your thoughts?
Message was edited by:
smalltalk

Hibernate (for example) actually does both.
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Certainly get is the more commonly used of these methods.
If you are returning something like an array I believe it is always preferable to return a zero length array rather than null to save the extra client code.

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Hi,
is there anyone who would like to share to strategies for avoiding persistence layer bottlenecks (lazy loading, for example).
I'm not really interested in discussing the technologies itself (like hibernate of jdo), but i'm sure really interested in what they do behind the scennes to make it work.
Thanks,
ltcmelo

Lazy loading is a good strategy that helps improve performance when your app is doing alot of reads.
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Frank,
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Is an anti-virus needed for a new macbook pro?

Is an anti-virus needed for a new macbook pro with retina display?

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Any website that prompts you to install a “codec,” “plug-in,” "player," "extractor," or “certificate” that comes from that same site, or an unknown one, is untrustworthy.
A web operator who tells you that you have a “virus,” or that anything else is wrong with your computer, or that you have won a prize in a contest you never entered, is trying to commit a crime with you as the victim. (Some reputable websites did legitimately warn visitors who were infected with the "DNSChanger" malware. That exception to this rule no longer applies.)
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Software of any kind downloaded from a BitTorrent or from a Usenet binary newsgroup is unsafe.
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Software with a corporate brand, such as Adobe Flash Player, must be downloaded directly from the developer’s website. If it comes from any other source, it's unsafe.
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Java is not included in OS X 10.7 and later. Discrete Java installers are distributed by Apple and by Oracle (the developer of Java.) Don't use either one unless you need it. Most people don't. If Java is installed, disable it — not JavaScript — in your browsers.
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Their design is predicated on the nonexistent threat that malware may be injected at any time, anywhere in the file system. Malware is downloaded from the network; it doesn't materialize from nowhere.
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A Windows malware attachment in email is usually easy to recognize. The file name will often be targeted at people who aren't very bright; for example:
♥♥♥♥♥♥♥♥♥♥♥♥♥♥!!!!!!!H0TBABEZ4U!!!!!!!.AVI♥♥♥♥♥♥♥♥♥♥♥♥♥♥.exe
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The ClamXav developer won't try to "upsell" you to a paid version of the product. Other developers may do that. Don't be upsold. For one thing, you should not pay to protect Windows users from the consequences of their choice of computing platform. For another, a paid upgrade from a free app will probably have the disadvantages mentioned in section 7.
9. It seems to be a common belief that the built-in Application Firewall acts as a barrier to infection, or prevents malware from functioning. It does neither. It blocks inbound connections to certain network services you're running, such as file sharing. It's disabled by default and you should leave it that way if you're behind a router on a private home or office network. Activate it only when you're on an untrusted network, for instance a public Wi-Fi hotspot, where you don't want to provide services. Disable any services you don't use in the Sharing preference pane. All are disabled by default.
10. As a Mac user you don't have to live in fear that your computer is going to be infected every time you install an application, read email, or visit a web page. But neither should you have the false idea that you will always be safe, no matter what you do. The greatest harm done by security software is precisely its selling point: it makes people feel safe. They may then feel safe enough to take risks from which the software doesn't protect them. Nothing can lessen the need for safe computing practices.

How to design model for staging layer.

Hi expert,
what is the rule when design staging layer? such as how much layer needed for staging? and what objects used in staging? why different layers needed for staging .etc.?

Hi,
Please have a look at SAP Help - Enterprise Data Warehouse (EDW) for basic information around layers and architecture. Moreover, please have a look at my blog Layered, Scalable Architecture (LSA) from an Implementation Perspective - Overview where you can find several "accelerators" to facilitate your implementation.
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Hi Experts,
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Regards,
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Hi Arnab,
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USE:
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Regards
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Need for persistence layer?

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