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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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 ...
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votes
4answers
6k 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?
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2answers
3k 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
3k 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 ...
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votes
2answers
6k 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 ...
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votes
2answers
3k 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
1answer
206 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?
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vote
1answer
968 views

ORA-00942: table or view does not exist while creating synonym

We are using oracle 11g, the db structure goes like this: We have users CST and FAS. CST contains a table ST_CAT2, a public synonym ST_CAT has been created for the table CST.ST_CAT2 as a SYS user. ...
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vote
1answer
601 views

Preloading a Java library in DB2, similar to ORACLE's loadjava

Edit to add details to clarify, based on Chris' comment: A Java stored procedure depends on external libraries. Locally it compiles successfully, since they are added to the classpath. But when ...
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3answers
83 views

Allowing users to compile / run PLSQL and SQL

As a DBA - assuming my users are knowledgeable with PLSQL and SQL - why would I not grant my users privileges to compile and run their own PLSQL code. We have an MI database environment where the data ...
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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 ...
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1answer
2k views

Why am I NOT getting a mutating table error in trigger?

It's (or at least was) known that you cannot use DML statements on a mutating table inside a trigger. An excerpt from the Oracle documentation: A mutating table is a table that is being modified ...
9
votes
1answer
1k views

Do Oracle databases use Java internally?

My question is fairly simple. Is Java used internally by Oracle in their DBMSs?
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2answers
4k 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 ...
7
votes
1answer
159 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 = ...
7
votes
1answer
36k views

How do I declare and use variables in Oracle?

My main skills are with SQL Server, but I have been asked to do some tuning of an Oracle query. I have written the following SQL: declare @startDate int select @startDate = 20110501 And I get this ...
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votes
2answers
5k views

How to extract Procedure, Function, etc. Source Code from an Oracle Export

I have generated an EXPDAT.DMP file of an Oracle database with the command: exp userid=usr/pass@db owner=own rows=n compress=n I then ran the following command to generate a file containing the ...
7
votes
1answer
909 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 & ...
6
votes
1answer
2k 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 ...
5
votes
1answer
688 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
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1answer
571 views

Silent truncation of last character when using SSIS with Oracle

I am using SSIS to export data from an Oracle database. Sometimes when I export a VARCHAR2 column to NVARCHAR the last character gets truncated (silently). It's completely random as far as I can tell. ...
5
votes
2answers
638 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
8k 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
3answers
751 views

TNS-12541 Error

I have grid installed in my pc but the problem is LISTENER does not start automatically. I have to start listener manually and then only LISTENER get started. But before starting listener if you check ...
4
votes
1answer
453 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
8k views

Oracle: Non key-preserved table should be

I'm getting "ORA-01779: cannot modify a column which maps to a non key-preserved table" when I try to update a join. I've searched around the site and found a lot of advice on what key-preserved ...
4
votes
1answer
6k 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 ...
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2answers
6k views

In Oracle how do you move a Schema to a different Tablespace?

I noticed that a Schema has been created in the USERS Tablespace but our local rule is that it should be in a Tablespace by itself. In Oracle how do you move a Schema to a different Tablespace?
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3answers
5k 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
3answers
2k views

OCIEnvCreate failed to create environment handle after installing oracle_fdw

I have installed oracle_fdw successfully. After I create extension oracle_fdw and foreign table it shows the following error. Is this a server configuration problem? --env Oracle : 10.2.0.1 ...
4
votes
1answer
1k 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
8k 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
2k 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
2answers
666 views

Resources for SQL Server developer migrating to Oracle

What resources can you recommend for a SQL Server developer wanting to learn Oracle basics? I am looking for a comprehensive whitepaper or blog post describing differences between these systems and ...
4
votes
2answers
1k 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
2k views

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

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
1k 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
1k views

DB2 (LUW) equivalent for Oracle “drop user cascade”

This question is related to creating and initialising test and development databases for an application that has the database running on LUW (linux-unix-windows) On oracle, we have an os user (on ...
3
votes
1answer
2k views

How To dump data from Oracle to Vertica

I want to transfer data from Oracle to Vertica and I want to know what is best way to do it? I s there a tool for it? I tried to dump the Oracle data and load it to Vertica using 'Copy Direct' ...
3
votes
2answers
20k 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
4answers
7k 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
2answers
25k views

ORA-12505: TNS:listener does not currently know of SID given in connect descriptor

Couple of days back, I execute shutdown on my DB but it took very long time so I shutdown my m/c. After restarting my machine, I get this exception when I try to connect to my database using TOAD. I ...
3
votes
5answers
8k 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
640 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 ...
3
votes
2answers
8k views

Oracle 10g dump file push into Oracle 11g database

Currently when executing the imp command with the following parameters: file=my.dmp log=my.log fromuser=myuser touser=myuser The following errors occur: IMP-00058: ORACLE error 12560 ...
2
votes
0answers
80 views

ORA-00937 when calculating a sub-value in an aggregate select statement

The problem described below applies to Oracle 11g databases. I also tested the statements on MySQL and PostgreSQL with no problems of the kind mentioned in this question. I want to use an ...
2
votes
2answers
247 views

Design of an application log database

We are generating logs like following example(this is a table no actual pipes): 2014-06-10 09:00:03.457 | Channel1 | Operation3 | Function15 | 15ms 2014-06-10 09:00:08.245 | Channel2 | Operation5 | ...
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0answers
118 views

Oracle: separate column histograms for partitions

I have a partitioned table like MY_TABLE(PART_KEY, DATE_KEY, ...) with a local partitioned index on (PART_KEY, DATE_KEY). When I collect stats on the table, I end up with a HEIGHT BALANCED histogram ...
2
votes
1answer
893 views

Oracle 11g installation stuck at installation

I'm trying to install oracle 11g on fedora by following this tutorial but it stuck after I click Next in step 8. The screen does not go away even after several hours. There's no log file in ...
2
votes
1answer
914 views

Oracle idle connections lost

I have a problem with an Oracle 11g instance. Every connection that has been idle for about 20 minutes are lost. I get the following error ORA-03135: connection lost contact I did the following ...