Oracle is a RDBMS (Relational Database Management System) created by Oracle Corporation. It supports a large number of languages and application development frameworks. Its primary languages are SQL, PL/SQL and Java. Also included is support for C (Pro*C, OCI and EXTPROC), C++ (OCCI) and Java (JDBC) ...

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oracle - list users with access to certain tables

I'm sure this has been asked before but I can't seem to find the relevant details for the following. Is there some sort of pre-built table that can do the following (I have used dba_tab_privs but it ...
8
votes
3answers
4k views

How to differentiate between SQL and PL/SQL?

I know the question might sound too stupid, but I never understood this part. SQL*Plus works with both SQL and PL/SQL. How do I know whether some code is SQL or PL/SQL? If my code has a for ...
11
votes
5answers
15k views

Best way to delete very large recordset in Oracle

I manage an application which has a very large (nearly 1TB of data with more than 500 million rows in one table) Oracle database back end. The database doesn't really do anything (no SProcs, no ...
10
votes
7answers
6k views

Tools to monitor Oracle Database Performance on Standard Edition

Here is what I am looking for: Works on Standard Edition i.e. No Diagnostic Pack. Provides both current and historical performance data. Good visuals for easy spotting of trends and presentation ...
9
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2answers
3k views

Script out Oracle DDL in an automated fashion

Oracle SQL Developer is able to export DDL through Tools -> Database Export... This works very well, but requires manual intervention. I know of DBMS_METADATA.get_ddl(), but have found that the ...
6
votes
2answers
888 views

Database for building a realtime analytics system

I want to build a system similar to Google Analytics (only used for internal use, less traffic and less feature), and mainly focus on Real time counting of unique URI visit/PV by different ...
4
votes
2answers
5k views

How to catch and handle only specific Oracle exceptions?

From this and this i guess, that there is no predefined Named System Exceptions for ORA-00955. How can I rewrite the following to catch only the error ORA-00955? begin EXECUTE IMMEDIATE ...
11
votes
7answers
27k views

Import a Oracle DMP file into a Fresh install of oracle

A client sent us a oracle database we need to test against. We don't use oracle or have any oracle expertise in house. We need to setup the database so we can connect to it and debug a problem. I ...
8
votes
3answers
866 views

How can I ensure that only one copy of a procedure is running in Oracle?

We have the need to ensure that only one copy of a particular procedure is running in Oracle. If it is already running and a user tries to open another, then it should error. Whats the best method ...
2
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1answer
1k views

Oracle 10gR2 to 11gR2 upgrade - performance hit [closed]

We've recently upgraded from Oracle 10gR2 (10.2.0.4 ) to 11gR2 (11.2.0.3) and we are noticing a significant hit in performance although execution plans are the same for the offended queries before and ...
21
votes
4answers
7k views

Why is OS authentication considered poor security for Oracle databases?

Oracle is deprecating OS authentication according to the Oracle Database Security Guide, which says Be aware that the REMOTE_OS_AUTHENT parameter was deprecated in Oracle Database 11g Release ...
8
votes
2answers
922 views

Oracle Shutdown Method

Shutting down a database before doing an upgrade or a patch can be done several ways. shutdown immediate; or shutdown abort; startup restrict; shutdown immediate; or shutdown abort; startup ...
8
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2answers
2k views

Why can't I read Oracles CLOB columns via SQL-SERVER 2008 linked server?

I want to access data in an Oracle 11g database from SQL-Server 2008 I set up a linked server and when I execute select * from [Link_server_name]..Oracle_schema.Oracle_table and Oracle_table ...
7
votes
2answers
3k views

Oracle 11g: performance improvements of inserts

I have a table of 500 millions of rows (and growing) I did the following to improve performance of inserts: On database side: dropped all indexes and constraints disabled logging On application ...
6
votes
2answers
2k views

Oracle 10g - How to prevent one user from hogging all resources?

I am wondering if there is any way to limit how much resources one user can take on my Oracle system. I want to limit some queries and systems from being able to hog all system resources when they run ...
5
votes
2answers
3k views

Database logon trigger

To block a particular user and IP combination on an Oracle Database , I created the following trigger, and compiled without errors. Create or replace trigger you_may_not_login after logon on database ...
4
votes
3answers
572 views

Is Oracle DB immune to the InnoDB deadlocks found in MySQL?

It seems odd to me that MySQL would not handle this internally: "Deadlock found when trying to get lock; try restarting transaction" Does Oracle DB work around this issue? After all, Oracle owns ...
4
votes
2answers
2k views

How to handle multiple Oracle homes?

On my desktop I have an Oracle client and and Oracle ODAC installed in different homes. I need ODAC because there ADO components off the Client installation don't work correct with CLOB data. I think ...
3
votes
1answer
822 views

Oracle: Full database (user) restore requires drop?

In our development environment (Oracle 11g), we often have to restore databases (users) to previous versions to test upgrades, verify defects, etc. We are using expdp/impdp to perform our ...
3
votes
2answers
715 views

A database in MySQL is a schema in Oracle : I do not understand this statement

Please help me understand this statement: A database in MySQL is a schema in Oracle. I have just started to use Oracle and I find it different from other RDBMS softwares I have used like MSSQL, ...
3
votes
2answers
3k views

Estimate a Database Size

I have to do some project, and need to estimate the DB size. I'm gonna to use Oracle in the project, because will have a lot of transactions and size. But in the "presentation" I need to specify, in 5 ...
3
votes
1answer
9k views

How can I import the contents of an Oracle database into Visio to create an Entity Relationship Diagram?

I have an Oracle database, and I would like to create an ERD in Visio 2007 Pro. I have so far looked at DBMS_METADATA.GET_DDL commands to generate ddl. I know that I can import an Access DB into ...
2
votes
2answers
1k views

Querying a database efficiently for a huge chunk of data

Here is my query SELECT * FROM ( SELECT a.*, rownum rnum FROM ( SELECT id, data FROM t ORDER BY id ) a ...
2
votes
2answers
3k views

Troubleshooting Oracle ORA-08103 - object no longer exists

I am getting this error from Oracle intermittently. A trigger is truncating a partition from a partitioned table while a long-running query is running against it. Since I'm truncating a different ...
1
vote
1answer
197 views

SQL from/where or join?

I was wondering performance wise what would be faster a join or a from and where query. I am trying merge and update query but performance is terrible?
0
votes
3answers
413 views

Can a RDBMS connect to a remote server, execute a select query and copy them into a local table just with SQL commands?

I'm sorry it may sound stupid but I've been wondering about how multiple databases are automated before the virtualization era. Can a DB Adminsitrator make a stored procedure to get data from a remote ...
10
votes
2answers
2k views

Security for Application Developers doing PL/SQL work in Oracle

How do you handle the lack of Schema level privileges in Oracle? Oracle’s security architecture works well for applications that only need object level privileges and it works well for DBAs that need ...
9
votes
2answers
2k views

Updating 700 million rows to same value

I've got a data warehouse (oracle) where I need to set a column to the same value for all 700 million rows. I don't have admin access, or access to an admin, so this needs to be accomplished with ...
8
votes
1answer
677 views

Do Oracle databases use Java internally?

My question is fairly simple. Is Java used internally by Oracle in their DBMSs?
7
votes
1answer
147 views

Cardinality is so far off from reality

I've got a table where the cardinality for plans just seems waaaaaay too high - despite updating stats and even trying dynamic sampling for Oracle 11gR2. select count(*) from table1 where col1 = ...
6
votes
4answers
1k views

Multiple operations using WITH

Is there a way to execute multiple operations using the WITH statement? Something like WITH T AS ( SELECT * FROM Tbl ) BEGIN OPEN P_OUTCURSOR FOR SELECT * FROM T; SELECT COUNT(*) INTO ...
6
votes
1answer
718 views

Materialized views in oracle

How are materialized views implemented in oracle? I've created a materialized view in oracle. What I now see is a quite normal table with a job. Are materialized views translated into tables & ...
5
votes
1answer
291 views

Enforce data integrity with a recursive table

I have an existing oracle 11g database schema that works with a web application. I am planning an expansion to the application so a web service can do data operations on the database. As part of the ...
5
votes
3answers
491 views

How to store many smallish time-series in a relational DB?

Input Data Multiple Tests Beds generate measurement data of various complexity. In it's most basic form, not considering any meta-data, one measurement on a Test Bed will be a small (1 - a few ...
5
votes
2answers
469 views

Oracle Advanced Queuing LIFO

With Oracle's Advanced Queuing is there a way to dequeue messages in a LIFO (last in first out) order? There is an indication through a lack of information that this is not an option, but perhaps ...
5
votes
2answers
4k views

Why do we need to backup Oracle archive logs along with datafiles

Oracle® Database Backup and Recovery Basics 10g Release 2 (10.2) says that Archived redo logs are the key to successful media recovery. Back them up regularly. But, I wonder, why backups of ...
4
votes
1answer
234 views

Unable to connect oracle as sysdba tables have been dropped

I have a script which lists all tables belonging to the user and executes DROP for all of them. By mistake, I logged in oracle with 'sys as sysdba' and ran above script. Due to which all sysdba ...
4
votes
1answer
3k views

How can I view what NLS settings are active for other session?

I've got another session that I suspect isn't running with the 'proper' NLS settings for us in Oracle 11gR2. What can I query to show the NLS settings for a different active session - all of the ...
4
votes
3answers
2k views

Is (and if how) it possible in Oracle to “insert into <table> values <rowtype-variable>” if <table> has virtual columns

Here's a table create table tq84_virtual_test_without ( col_1 number, col_2 number, col_3 number, col_4 number, col_5 number ); with the rule that col_5's value is the sum of the other ...
4
votes
1answer
752 views

What is Sql Server Clustered Index in Oracle terminology

A clustered index in sql server like a dictionary or telephone directory. A,B,C,D it goes on. If you look up with a name Ozgur you start O then z etc. I would like a simple explaination for this ...
4
votes
1answer
4k views

oracle format specifiers: to_number vs to_char

SQL> select TO_NUMBER(123.56,'999.9') from dual; select TO_NUMBER(123.56,'999.9') from dual * ERROR at line 1: ORA-01722: invalid number SQL> select TO_CHAR(123.56,'999.9') ...
4
votes
1answer
1k views

How do I horizontally partition an oracle database table, and should I?

We have a tenanted data warehouse that we are doing reporting on. Queries are beginning to take a long time, and we're looking at options to reduce this. There are two thoughts at the moment. Create ...
4
votes
1answer
717 views

What is the difference between these two create table statements?

a) SQL> CREATE TABLE xml_tab1(poDoc XMLTYPE); Table created. SQL> desc xml_tab1; Name Null? Type ----------------------------------------- -------- ...
4
votes
2answers
1k views

What's a free client for Oracle 8 on Linux / Ubuntu?

I need to connect to a legacy Oracle 8 database. Oracle SQL Developer would be my tool of choice, but the current version doesn't support Oracle 8 anymore. I tried Squirrel too, but the connection ...
3
votes
1answer
287 views

How to separate out individual sql statements from Oracle SQL script for execution from java code

I have Oracle DB 11g Enterprise Edition and I want to execute sql script from my java code. I am reading this sql script from a .sql file and the script contains statements such as create table, ...
3
votes
2answers
6k views

Using Same CASE WHEN Conditions For Multiple Query Columns

Is there a "better" way to rewrite a SELECT clause where multiple columns use the same CASE WHEN conditions so that the conditions are only checked once? See the example below. SELECT CASE ...
3
votes
1answer
7k views

Is commit necessary after DML operation in Function/Procedure?

I wonder to know if it is necessary to write commit after insert/delete/update in function/procedure? Example: create or replace function test_fun return number is begin delete from a; return ...
3
votes
4answers
4k views

Synchronizing data between MySQL and Oracle databases?

I want to sync data between Oracle & MySQL databases. What is the best possible way to achieve this? Are there any tools/software available? This is not a one-time but an ongoing operation. The ...
3
votes
5answers
5k views

Copying Oracle 11g express Database from one server to another

Basically, I am a MS-SQL developer,and relatively new to Oracle. Even after great deal of research, I was unable to find any way of copying entire database from one server instance to another. In ...
3
votes
1answer
385 views

What is an Effective Way to Count the Number of Pages in Oracle?

We've implemented paging in our PL/SQL procedures by building a dynamic SQL query and then selection only a portion of results. We build implement paging by putting the original query inside a ...