Performing database operations using EJB 3.0

I need to create a session bean that will perform operations on backend database. I am new to EJB 3.0 and need a gentle guidance to the solution
This is what I believe is suppose to be done
1. Create stateless bean interface marking operations.
2. Create bean implementation for above
3. Init stage will require me to connect to the Oracle database. Now am confused how will it get the connection details? Is there a way to extract the url username and password using resource bendle which can be accessed from within bean implementation?
4. Bean method will perform update, read oprations
5. Predestroy will close the connection
6. A client will simply call this ejb with some input parameter(s)
Please let me know if am doing anything wrong here

If you use EJB technology for which it is designed, the container (server) will manage the transaction (and also the connections to the database) for you, so no creation or cleanup of connections on your part. I advise you to read into JPA which is designed to be used in conjunction with EJB tech. The books Enterprise Javabeans 3.0 and Pro EJB 3: the Java Persistence API may help you a lot.

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We need to develop an on-line application which requires us to load input data
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Hi Corona,
"Corona Fang" <[email protected]> wrote in message
news:3f3b0ea3$[email protected]..
We need to develop an on-line application which requires us to load inputdata
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Use the schema attribute of the Table annotation:
package javax.persistence;
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[url=http://www.google.com/search?hl=en&ie=UTF-8&q=squa
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I need a clarification : Can I use EJBs instead of helper classes for better performance and less network traffic?

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thank you,
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Please suggest me which method (is Helper classes or Using EJBs) is perferable :
1) to get better performance
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2) for less network traffic
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Error: the database could not be exclusively locked to perform the operation in sql server 2008 ?

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Thanks.

as mentioned earlier by both these users just wait for all the connections to go and then try- it will succed
or else if it is dev\Uat environment & you can kill the conenctions - make the changes (use this as last option)
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Sarabpreet Singh Anand
Blog ,
Personal website
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Hi, I have a hard disk failure so to recover my data I am using disk utility to restore the data on an external drive while booting from a second external hard drive. When I perform the operation it gives me an input/output error and stops. Any tips?

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Disk Utility only creates a image of the drive, so it's no help getting exactly what you want, which is your files. If the file structure is messed up or the drive is failing then it's no help.
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Hello Experts,
I am getting an error while performing database point in time recovery multiple times using RMAN. Details are as follows :-
Environment:
Oracle 11g, ASM,
Database DiskGroups : DG_DATA (Data files), DG_ARCH(Archive logs), DG_REDO(Redo logs Control file).
Snapshot DiskGroups :
Snapshot1 (taken at 9 am): SNAP1_DATA, SNAP1_ARCH, +SNAP1_REDO
Snapshot2 (taken at 10 am): SNAP2_DATA, SNAP2_ARCH, +SNAP2_REDO
Steps performed for point in time recovery:
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3. Catalog data files from snapshot 1.
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Results:
Recovery 1: At 10.30 am, I performed first point in time recovery till 9:30 am, it was successful. Database incarnation was raised from *2* to *3*.
Recovery 2: At 11:10 am, I performed another point in time recovery till 9:45 am, while doing it I reset the incarnation of DB to *2*, it failed with following error :-
Starting recover at 28-FEB-13
using channel ORA_DISK_1
starting media recovery
media recovery failed
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of recover command at 03/06/2013 11:10:57
ORA-00283: recovery session canceled due to errors
RMAN-11003: failure during parse/execution of SQL statement: alter database recover if needed
start until time 'MAR 06 2013 09:45:00'
ORA-00283: recovery session canceled due to errors
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ORA-00312: online log 1 thread 1: '+DG_REDO/orcl/onlinelog/group_1.257.807150859'
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ORA-15012: ASM file '+DG_REDO/orcl/onlinelog/group_1.257.807150859' does not exist
Doubts:
1. Why did recovery failed 2nd time, but not 1st time and why is RMAN looking for online redo log group_1.257.807150859 in 2nd recovery ?
3. I tried restoring control file from AutoBackup, in that case both 1st and 2nd recovery succeeded.
However for this to work, I always need to keep the AutoBackup feature enabled.
How reliable is control file AutoBackup ? Is there any alternative to using AutoBackup, can I restore control file from snapshot backup only ?
4. If I restore control file from AutoBackup, then from what point of time/SCN does RMAN restores the control file ?
Please help me out in this issue.
Thanks.

992748 wrote:
Hello experts,
I'm little newbie to RMAN recovery. Please help me in these doubts:
1. If I have datafiles, archive logs & control files backup, but current online REDO logs are lost, then can I perform incomplete database recovery ?yes, if you have backups of everything else
2. Till what maximum time/scn can incomplete database recovery be performed ??Assuming the only thing lost is the redo logs, you can recover to the last scn in the last archivelog.
3. What is role of online REDO logs in incomplete database recovery ? They provide the final redo changes - the ones that have not been written to archivelogs
Are they required for incomplete recovery ?It depends on how much incomplete recovery you need to do.
Think of all of your changes as a constant stream of redo information. As a redolog fills, it is copied to archive, then (eventually) reused. over time, your redo stream is in archivelog_1, continuing into archvivelog_2, then to 3, and eventually, when you get to the last archivelog, into the online redo. A recovery will start with the oldest necessary point in the redo stream and continue forward. Whether or not you need the online redo for a PIT recovery depends on how far forward you need to recover.
But you should take every precaution to prevent loss of online redo logs .. starting with having multiple members in each redo group ... and keeping those multiple members on physically separate disks.

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Hi
I have an urgent requirement. I have a table with Spatial column. I have generated Business components based on Spatial Table.
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HI,
see this example.
u can do like this.
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SELECT carrid connid seatsocc
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bharat.

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Dear All,
I am getting an error like 'The Connection can not be used to perform thsi operation, it is either close or Invalid in this context.
Below is the code what am using:
Sub Select_Query()
Dim SQL_String As String
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Dim cn As ADODB.Connection 'Declaring Connection
Dim cmdobj As ADODB.Command 'Declare command Object
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count_value = WorksheetFunction.CountA(Worksheets("Payments").Range("A:A"))
For i = 4 To count_value
SQL_String = Worksheets("Payments").Range("AA" & i).Value
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rs.CursorLocation = adUseClient
rs.Open SQL_String, cn, adOpenForwardOnly, adLockOptimistic, adCmdText
Dim val As Integer
val = rs.recordCount
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cn.Close
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'con.Close
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And select statment is picking one of the sheets, and SQL query is:
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WHERE sa.sa_id = ss.sa_id
AND ss.sp_id = sp.sp_id
AND sp.sp_id = spg.sp_id
AND spg.geo_type_cd LIKE '%RR%'
AND spg.geo_val ='"&B4&"'
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Regards,
Prasad

Please, this is a Oracle forum, not a VBA forum. Mark this thread as answered and post it in a VBA forum.

Performing database operations using EJB 3.0

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