Read/Write Oracle database

Hello all,
I was thinking about having a look at reading from and writing to tables in an Oracle DB.
Immediately I thought about using JCA, but then started thinking... Is JCA only a method of running RFC enabled functions? I used JCo before to connect to R3 and run an RFC enabled function to read from tables. Since Oracle is a DB I'm assuming that it doesn't have functions to be run, just tables to be read/written.
So then I'm thinking JDBC. Is this the way for me? I know that using JDBC will require that I have access to Oracle JDBC drivers, are these freely available or proprietary?
Do any of you have experience with this? It sounded as though it would be so straight forward at first....
As always, any help is greatly appreciated.
P.

Hi Patrick,
you can use JCA as well as JDBC. In my eyes the JCA way is a bit anti-standard, because most frameworks doing persistance stuff for you use JDBC, so it's the more natural way; at least, if you won't ever change the fact that you are accessing a DB (and won't retrieve data some day via another kind of EIS). Anyhow, even JCA uses JDBC if the EIS is a DB...
For the JCA way, there have been some examples here on SDN in December, it's a pity, I don't find them anymore. Anyhow, I didn't find them very intuitive.
For JDBC, see for example this topic: How to retrieve data from a MSSQL?
If you have Oracle, you also will have Oracle Drivers. Alternatively, you can use the SAP Oracle Drivers, see Configuring JDBC Driver for JDBC System
Hope it helps
Detlev

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I am planning to take this exam and I have several questions:
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4) To use external tables, is only read grant on the directory necessary or also write?
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#1) well, the manual is free; find here the SQL Language Reference - http://www.oracle.com/pls/db112/portal.all_books#index-SQL
#2 & 3) If you proved it yourself, that settles it!
#4) Here's a good article about external tables: http://www.oracle-developer.net/display.php?id=512
I noted this paragraph in it, which might answer your question:
In addition to the standard read-write Oracle directory that we need for our external table, we also need an additional executable directory object for the preprocessor. This directory defines the location of the executables used by the preprocessor (we will be using gzip below). As far as Oracle is concerned, an executable directory is one that has EXECUTE privileges granted on it (this is an 11g feature specifically to support the preprocessor).
#5) don't know

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Hi,
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Since ive already given 1Z0-007 for PL/SQL Developer, so do i need to give the exam once again for Oracle Database 10g Administrator???No. The one pass if good for both OCA tracks, so you only now need to pass 1z0-042 for your DBA OCA as you already have a 1z0-007 pass.
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Hi
I want to write Oracle database with database toolkits;
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Attachments:
Oracle DB.vi ‏36 KB

Frankly I have never seen this problem, but then I make a point of never using the database connectivity toolkit. Assuming a Windows platform, Windows implements something called connection pooling so when you "close" a connection the OS inserts it into a pool so If you ask for another connection it doesn't actually open a new one it just gives you back a reference to one of the ones you "closed" before.
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What version of Oracle?
Is the instance of Oracle local or on another computer?
How are you communicating with Oracle (odbc, oledb, etc)?
Mike...
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Certified LabVIEW Architect
LabVIEW Champion
"... after all, He's not a tame lion..."
Be thinking ahead and mark your dance card for NI Week 2015 now: TS 6139 - Object Oriented First Steps

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Thanks and Regards
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Hai,
I am suggesting the solution.
I will try out and let u know soon.
Make a coma separated file from your excel file.
Assuming that your requirement allows to make a csv file.
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How to read\write text file into oracle database.

Hello,
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Here is a web page with easy to follow instructions regarding external files: http://www.adp-gmbh.ch/ora/misc/ext_table.html.
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Hi,
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startup;
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Hello,
There're features which allows you to open a Standby database in Read/Write mode but for all I know
it needs Entreprise Edition.
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a way by using flashback database so as to rolling backward the database and avoiding to recreate
the Standby.
In Standard Edition I'm afraid that you'll have to recreate your Standby database.
Best regards,
Jean-Valentin

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Hi All,
I am fairly new to database administration, so please bear with me if this is something that is simple or not achievable at all -
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c5b4a91d-d35a-43ba-ac96-6d1821541d33 wrote:
Hi All,
I am fairly new to database administration, so please bear with me if this is something that is simple or not achievable at all -
SetUp:
I have an Oracle DB on one dedicated Server, to which I only have a read_only access.
I have a MySQL database setup on a windows server 2008, both are on the company network and accessible to internal employees only.
Problem Statement:
I need to read certain tables from Oracle DB and push the records to MySQL database.
I have a stored procedure which was doing this but from one Oracle Schema to another, which is running fine, now I need to use the same stored procedure but read from one database (Oracle) and write to another database (MySQL), is there a way to do this through the stored procedure, I know I can write a java program to do this, but need to do it through a stored procedure.
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Start here: http://docs.oracle.com/cd/E11882_01/server.112/e25494/ds_concepts.htm#i1007709

SGA size is 1 GB free but oracle starts physical read/write,why ?

Dear Friends ,
In my production server I observe that it takes the the data from the HDD where my SGA is still 1 GB free .
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Edited by: shipon_97 on Mar 24, 2009 10:45 AM

shipon_97,
Your understanding is wrong. From your previous posts it appears you never read the concepts manual.
Begging on my knees PLEASE READ IT and stop asking doc questions.
Sybrand Bakker
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Free Report Writer for Oracle Database except Crystal Report and Data Vison

Dear All,
I want Free Report Writer for Oracle Database except Crystal Report and Data Vision software.
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Please check the following link -
http://www.google.co.in/search?client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&channel=s&hl=en&q=open+source+report+writer+for+oracle&meta=&btnG=Google+Search
Regards.
Satyaki De.

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And from the "Deployment Guide for Oracle on Windows using Dell PowerEdge Servers.pdf" in http://www.oracle.com/technology/tech/windows/index.html
RAID LEVELS I have heard that it is for disks where datafiles reside the following is true
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I would like to know
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Edited by: sandeshd on Oct 14, 2009 3:11 PM

We were in a similar situation some weeks ago, we decided to make a trigger (logout) for saving the butes for a specific schema, you can work with this data importing it with Excel or something similar.
DROP TABLESPACE BYTES_USUARIOS INCLUDING CONTENTS AND DATAFILES;
CREATE TABLESPACE BYTES_USUARIOS DATAFILE
'/oradata/oradata/ewok/bytes_usuarios.dbf' SIZE 1024M AUTOEXTEND ON NEXT 25M MAXSIZE UNLIMITED
LOGGING
ONLINE
PERMANENT
EXTENT MANAGEMENT LOCAL AUTOALLOCATE
BLOCKSIZE 8K
SEGMENT SPACE MANAGEMENT MANUAL
FLASHBACK ON;
+++++++++++
CREATE USER B1
IDENTIFIED BY VALUES %password%
DEFAULT TABLESPACE BYTES_USUARIOS
TEMPORARY TABLESPACE TEMP
PROFILE MONITORING_PROFILE
ACCOUNT UNLOCK;
-- 1 Role for B1
GRANT CONNECT TO B1;
ALTER USER B1 DEFAULT ROLE NONE;
-- 2 System Privileges for B1
GRANT CREATE TABLE TO B1;
GRANT CREATE SESSION TO B1;
-- 1 Tablespace Quota for B1
ALTER USER B1 QUOTA UNLIMITED ON BYTES_USUARIOS;
++++++++++
CREATE TABLE b1.BYTES_USUARIOS
USERNAME VARCHAR2(30 BYTE),
SID NUMBER,
SERIAL# NUMBER,
MACHINE VARCHAR2(64 BYTE),
LOGON_TIME DATE,
CLS VARCHAR2(53 BYTE),
NAME VARCHAR2(64 BYTE),
VALUE NUMBER
TABLESPACE BYTES_USUARIOS
PCTUSED 40
PCTFREE 10
INITRANS 1
MAXTRANS 255
STORAGE (
INITIAL 64K
MINEXTENTS 1
MAXEXTENTS 2147483645
PCTINCREASE 0
FREELISTS 1
FREELIST GROUPS 1
BUFFER_POOL DEFAULT
LOGGING
NOCOMPRESS
NOCACHE
NOPARALLEL
MONITORING;
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++++++++++++++++
grant select on v_$mystat to system;
grant select on v_$session to system;
grant select on v_$statname to system;
DROP TRIGGER SYSTEM.TRG_LOGOFF;
CREATE OR REPLACE TRIGGER SYSTEM.TRG_LOGOFF
BEFORE LOGOFF
ON DATABASE
DECLARE
--VAR_CADENA VARCHAR(20);
begin
--VAR_CADENA := "%bytes%";
--execute immediate '
insert into b1.bytes_usuarios (
select
ss.username,
ss.sid, ss.serial#, ss.machine, ss.logon_time,
decode (bitand( 1,class), 1,'User ', '') ||
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decode (bitand( 4,class), 4,'Enqueue ', '') ||
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decode (bitand( 16,class), 16,'Parallel Server ', '') ||
decode (bitand( 32,class), 32,'OS ', '') ||
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decode (bitand(128,class),128,'Debug ', '') cls,
name,(value/1024/1024) from sys.v_$statname m, sys.v_$mystat s, sys.v_$session ss
where
m.statistic# = s.statistic#
and (name like '%bytes sent%' or name like '%bytes received%')
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end;
++++++++++++
TODO
select username, name, sum(value)
from b1.bytes_usuarios
group by username, name
order by username, name
SOLO bytes enviados
select username, name, sum(value)
from b1.bytes_usuarios
where
and name like '%sent%'
group by username, name
order by username, name
SOLO bytes recibidos
select username, name, sum(value)
from b1.bytes_usuarios
where
and name like '%received%'
group by username, name
order by username, name

Write n then read xml from database to create graph in an applet

Hi mates
I have one problem I want show a trend(graph) from sql database which is having the records of about 8600 in a day. And i want to show a graph for a day
but sometimes it gives a problem like out-of-memory, so can anyone tell me how i can get read of it.
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can anytell me how to do it
any suggesion is appreciable
thanx

Here's are two example for what you are looking for
Re: Load xml data in Oracle table
Re: insert .xml file into xmltype table?
First you need to create a DIRECTORY object. That is how Oracle works and it expects a DIRECTORY object instead of a physical path when performing operations that read/write from disk. The directory path provided to the CREATE DIRECTORY command must be a directory that the machine Oracle DB resides on can see.
Then you can go either of two routes. You can INSERT that XML directly into a table, as shown in the second link I provided or you can read it into PL/SQL as the first link shows. Then in either case, you can use SQL to parse the XML for you.
Depending upon your needs, you may get better performance if you insert the XML into a table as the second link shows, assuming the XMLType column is stored as SECUREFILE BINARY XML.

File read/write in Oracle JVM

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Code:
try{
fwriter = new PrintWriter(new FileOutputStream("debugLog.txt",true));
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Thanks.
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A couple of suggestions:
1. (Please don't be offended...) I assume you have some stuff like:
fwriter.println("hello");
fwriter.flush();
fwriter.close();
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Oracle coherence first read/write operation take more time

I'm currently testing with oracle coherence Java and C++ version and from both versions for writing to any local or distributed or near cache first read/write operation take more time compared to next consecutive read/write operation. Is this because of boost operations happening inside actual HashMap or serialization or memory mapped implementation. What are the techniques which we can use to improve the performance with this first read/write operation?
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In which case, why bother using Coherence? You're not really gaining anything, are you?
What I'm trying to explain is that you're probably not going to get that "micro-second" level performance on a fully configured Coherence cluster, running across multiple machines, going via proxies for c++ clients. Coherence is designed to be a scalable, fault-tolerant, distributed caching/processing system. It's not really designed for real-time, guaranteed, nano-second/micro-second level processing. There are much better product stacks out there for that type of processing if that is your ultimate goal, IMHO.
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Just my two cents.
Cheers,
Steve
NB. I don't work for Oracle, so maybe they have a different opinion. :)

Read/Write Oracle database

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