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6
votes
3answers
4k views

Is it possible to see the (completed) SQL Statements executed by a specific session?

Is it possible to see a list of all past SQL statements executed by a specific session (or number of sessions)? For example, the following query gives me all currently executing statements from all ...
6
votes
3answers
6k views

ALTER SYSTEM DISCONNECT SESSION doesn't work

Oracle 11g. The devs leave sessions connected overnight, sometimes certain cron jobs fail because of that. I am trying to kill all user sessions, but I can't. I login as: sqlplus system/[password] ...
6
votes
2answers
1k views

Making the Oracle optimizer use a virtual column to find out about a partition

I have a large table that has three columns like this: "START_DATE" DATE, "START_VALUE" NUMBER(10,7) "START_DATE_VALUE" NUMBER(18,7) GENERATED ALWAYS AS ( (extract(YEAR FROM START_DATE) * ...
6
votes
1answer
402 views

Oracle Support Tips & Tricks

How can My Oracle Support (Metalink) be used effectively? What are your secret hints to this system? What saved you the most time?
6
votes
2answers
83k views

How to resolve ORA-01031: insufficient priviledges error on Windows installation?

I installed Oracle 11G on my Windows 2008 R2 Server. I also installed Oracle Client Libraries using separate installation media. After the client installation, when I try to log into the database ...
6
votes
1answer
3k views

MySQL or Oracle Associate Certification?

I have 15+ years in software development and 7+ in web development, and I want to get a certification in another area, like DBA. I have 7+ years of experience like MySQL developer. Which is better for ...
6
votes
1answer
181 views

Is Oracle Configuration Manager HIPAA compliant?

Does Oracle's Configuration Manager which according to Oracle provides a "40% faster issue resolution", violate HIPAA or require specific configuration in order to comply? This question concerns ...
6
votes
3answers
5k views

Add Oracle Label Security to an existing Oracle installation

We are using Amazon EC2 to host some Oracle database instances while we are evaluating and prototyping some software. We are using the AMIs provided by Oracle - specifically, Oracle Database 11g ...
6
votes
1answer
1k views

Using sys.diana and sys.pidl to parse PL/SQL

It seems to me that it should be possible to parse existing PL/SQL with the packages sys.diana and sys.pidl, but I have found nothing on the internet with the exception of a few scripts that seem to ...
6
votes
2answers
191 views

What is an Oracle ASSEMBLY?

What is an Oracle ASSEMBLY, in the context of Oracle SQL? It's listed in GV$SQLCOMMAND. Although GV$SQLCOMMAND is not a perfect guide to "real" SQL statements - for example it has UPSERT instead of ...
6
votes
1answer
758 views

What are the Oracle Dataguard Implications of Migrating to a PDB?

If I have an OLTP database with two physical standby instances (one remote) what are the implications of migrating the primary DB to being an Oracle 12c PDB? i.e. Does the process of migrating to ...
6
votes
1answer
442 views

Sudden increase in log_file_sync waits

I'm on Oracle 11gR2 with a 2 node RAC system. It's shared fiber storage to an EMC Clariion. Last friday things went bad..fast. All of the sudden processes that normally ran fine for years became ...
6
votes
1answer
22k views

How to free up disk space? which logs/directories to clean?

I want to free up the disk space on my Linux machine. I've drill down the space usage and found that the following directories have a big size /u01/app/11.2.0/grid/cv/log ...
6
votes
1answer
1k views

Global locking for multi-master Oracle GoldenGate replication

This is a very complex scenario, but I figured a state-of-the-art challenge might interest some of the many high-end users of dba.se. Problem I'm working on an intercontinental data replication ...
6
votes
3answers
3k views

Why would one need multiple instances of same Oracle database?

I came across following statement while reading this short article - An instance is the software (and memory) that Oracle uses to manipulate the data in the database. In order for the instance ...
6
votes
1answer
910 views

Package state not re-intialized on raise_application_error

When a package has state and the header is changed, the first call gets an error stack something like this: ORA-04068: existing state of packages has been discarded ORA-04061: existing state of ...
6
votes
2answers
4k views

SQL developer: Setup debugger for plsql

I'm trying to debug remotely pl/sql. But I can't - database returns me an error. What should I do to fix this and start debugging ? ORA-30683: failure establishing connection to debugger ...
6
votes
1answer
80 views

Parallel option performing worse on cluster

I'm trying out oracles parallel option on a cluster and surprisingly I am getting worse results with the parallel option. I was expecting some improvement with the parallel option but certainly not ...
6
votes
1answer
866 views

Find active values of SQLNET.ORA parameters on server

How can I find the active values of SQLNET.ORA parameters on the server? I know how to find the SQLNET.ORA file but there's no guarantee the values in that file are actively used. Parameter changes ...
6
votes
1answer
2k views

What is the meaning of “select * from relational(owner.table)”?

We recently got some errors in our alert log of the form 301598: Tue Jul 16 03:58:29 2013 301599: ORA-01555 caused by SQL statement below 301600: SELECT * FROM ...
6
votes
1answer
443 views

Update all rows

I want to know the most efficient manner to update every row in an extremely large Oracle table for a single column. For example: update mytable set mycolumn=null; or: update mytable set ...
5
votes
3answers
2k views

Alternatives to an INSERT Trigger

Looking for an example code in Oracle to do the same. i.e. Remove an insert trigger on table T1 whose job is to create a row in T2 based on the derived data. How would this PL-SQL api look like? ...
5
votes
3answers
29k views

What are the causes and solutions for mutating table errors?

I understand mutating table errors are caused by a design flaw or problematic query. An old query was recently put into production which throws a mutating table error. Our DBA solved the problem but ...
5
votes
2answers
2k views

What storage engines work with Oracle?

http://en.wikipedia.org/wiki/Database_engine mentions about database engines aka storage engines. What all storage engines can be used with the Oracle database?
5
votes
4answers
9k views

Why does = NULL not work in Oracle?

I recently realized that we need to use a special syntax IS NULL to compare a literal to NULL. Why does = NULL not work here?
5
votes
3answers
944 views

For Oracle, we mount the instance to the database or mount the database to the instance?

The following text is extract from oracle documentation. Start the instance, and mount and open the database. This can be done in unrestricted mode, allowing access to all users, or in ...
5
votes
1answer
5k views

how to use dual foreign key in oracle 10g

I have created two tables create table ref1(id varchar2(3) primary key); create table ref2(id varchar2(3) primary key); Now I want to create a third table with a single column as foreign key for ...
5
votes
1answer
5k views

How can I query names using regular expressions?

How could I search for a specific pattern in a column? For example, I like to get all user names that start with either letter A or B. (btw: this is tagged oracle, but it might be interesting in ...
5
votes
2answers
15k views

What is Key Preserved Table concept?

I read in the Oracle Documentation about key-preserved table in Updating Join Views Section. However, I didn't find any simple to way understand it. I hope to receive some simple conceptual details ...
5
votes
2answers
688 views

Defining constraints in `CREATE TABLE` statements

Recently I have been using a Database Abstraction Layer built by a Python web-framework called web2py (click for their DAL syntax). They include the option to include your constraints within the ...
5
votes
1answer
10k views

Why I don't need to COMMIT in database trigger?

We can't COMMIT/ROLLBACK in DML triggers because transaction is handled manually after DML statement. However, database triggers seems to be an exception. For example, suppose there's a database ...
5
votes
2answers
24k views

How to set an Oracle user's default schema?

I created a few new users in Oracle. However, when running sqlplus, they all need to fully qualified the table names in query. What's the best way to set a default schema for these new users?
5
votes
3answers
662 views

What are the top 5 design decisions which need to be made when implementing a database?

I am implementing an Oracle System to store event alerts from an application so I guess all the schema, database design will be handled by the application through a sript. I am new to Database ...
5
votes
4answers
15k views

Building Dynamic Oracle Where Clause

I'm working on application that uses dynamic query to do a select statement based on user input, after discussing security with DBAs they want me to convert my dynamic select statement into Stored ...
5
votes
4answers
175 views

Replicating only changes made by a specific database user

I am performing parallel testing. We have upgraded the legacy batch jobs to a new framework which we need to test against the existing batch jobs. In the existing setup, I have web application which ...
5
votes
4answers
242 views

What's the best way to list groups of values that are contained in other groups

For example, starting with a table like this: create table t as select 'A' as x, level as y from dual connect by level<=5 union all select 'B' as x, level+2 as y from dual connect by level<=5 ...
5
votes
5answers
19k views

Simplified/automated datafile free disk space reclaim

On Oracle version 11g: After Googling, I can't find a simple way to reclaim free space after deleting a table. I've found a lot of explanations, telling how the datafile becomes fragmented, the big ...
5
votes
3answers
1k views

Alternative for OPTIMIZER_FEATURES_ENABLE

I've installed a PHP driven application in a client's 9i server (Oracle9i Release 9.2.0.1.0 - 64bit Production). Certain queries are having an awful performance (it can use from 15 minutes to hours ...
5
votes
3answers
896 views

Database replication and consistency check

I got a question about 2 databases (oracle 10g) that I have, let's call them A and B. A have some information(in various tables) and I want B to get a partial copy of some tables from A, and ...
5
votes
2answers
25k views

Oracle Enterprise Manager 11g dbconsole “Internet Explorer cannot display the webpage”

The dbconsole is configured and started, but when I navigate to it, Internet Explorer shows the page stating that "Internet Explorer cannot display the webpage". This is the error that means that IE ...
5
votes
1answer
6k views

Export table without BLOB column

I have a big table with BLOB objects and some references from other tables to this one. I prepare dev and test schema for my app by making expdp (data pump) from production, then anonymizing data on ...
5
votes
2answers
5k views

Does order matter for composite primary key in Oracle or any database?

I have a Composite Primary key which is combination of Column1, and Column2. What would be the difference if I have Composite key with Column2, and Column1. Does it even really matter which order ...
5
votes
2answers
4k views

What is the difference between ROLE and PRIVILEGE for Oracle?

Is role a collection of certain privileges?
5
votes
3answers
5k views

Using the same sequence twice in a PL/SQL statement

I wrote the snippet of PL/SQL today: declare first_id number; second_id number; begin insert into table (sort_nr, text_id, unit_id) values(..., table_seq.nextval, table_seq.nextval) returning ...
5
votes
2answers
28k 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 ...
5
votes
4answers
166 views

Getting the value of 'foo' for the closest previous row with higher 'bar'

From this initial data: select level as foo, mod(ora_hash(level),4) as bar from dual connect by level<9; /* FOO BAR ---------------------- ...
5
votes
1answer
602 views

If an 'after' DDL trigger causes an error, is the DDL rolled back?

It has been suggested that DDL is logically performed something like this: begin COMMIT; perform any appropriate pre-DDL trigger code; do the ddl; perform any appropriate post-DDL ...
5
votes
3answers
7k views

PostgreSQL vs. Oracle High Availability solutions?

PostgreSQL has a matrix of different high availability options which represent many different ways of building replication into an RDBMS. Here is the PostgreSQL High Availability, Load Balancing, ...
5
votes
2answers
2k views

Oracle clean up

I have an Oracle database on a VMWare image that seems to be slowly eating all my available disk space. I would like to know if there is a command or script that would perform some kind of clean up of ...
5
votes
3answers
1k views

What could be the reason for disallowing a sub query in the values clause?

For example SQL> create table dates(d date); Table created. SQL> insert into dates select sysdate from dual; 1 row created. SQL> select * from dates; D --------- 28-MAY-11 SQL> ...