Ask the Experts

Ask the Experts

• Information on OUI (Oracle Universal Installer)

  What is the OUI tool? How can I find it?  Continue Reading

• Problems connecting to iSQL*PLUS

  When I click on TARGETS|DATABASES|TESTDB|ISQL*PLUS I get the following error message: "HTTP 404 NOT FOUND."  Continue Reading

• Move tables from system tablespace to users tablespace

  How to move tables from the system tablespace to the users tablespace in Oracle 8.0.6?  Continue Reading

• Cannot create services in Oracle 9i

  I am trying to create a database manually in Oracle 9i. I successfully created a password file but am unable to create services.  Continue Reading

• Migrate Oracle 9i data on Sun to 10g on Windows

  I need to migrate only data from a Sun machine with Oracle 9i to Oracle 10g on a Windows 2003 Server environment.  Continue Reading

• How to encrypt stored passwords in Oracle 8i?

  Does Oracle 8i have the ability to encrypt stored passwords?  Continue Reading

• ORA-01103 error during Oracle 10g startup

  I am installing Oracle 10g on Red Hat Linux. During startup I am getting the following error: "ORA-01103: database name 'SEEDDATA' in control file is not 'ORADB.'"  Continue Reading

• Retrieve last row inserted into table in Oracle

  How can I retrieve the last row inserted into a table? I don't want to have to specify the row number and I can't change the structure of the table.  Continue Reading

• Tool in Oracle 10g to keep track of execution of queries

  How can I keep track of the execution of stored procedures, functions and queries in Oracle 10g, as I used to do using SQL Server Profiler? Is there any tool in 10g for this purpose?  Continue Reading

• Total Oracle CPU time

  I'd like to know the amount of Oracle CPU time and I'm looking at the value for "CPU used by this session" in v$sysstat. Can I consider this as a total CPU time value?  Continue Reading

• How to increase SGA_MAX_SIZE in Oracle

  How to increase SGA_MAX_SIZE in Oracle? I got the error "ORA-03113: end-of-file on communication channel" during startup.  Continue Reading

• Simple SQL query takes longer than usual

  A simple SQL query is taking a longer time than it usually takes. How do we need to check to find out why it is taking so long?  Continue Reading

• Using RAID 5 with Oracle Database

  Is RAID 5 good for an Oracle database?  Continue Reading

• UPDATE only rows which match another table in SQL

  I have a SQL query where I am trying to update a column in a table from data in another table. This works fine when I try to update all the records in the first table; however, Is it possible to update only the missing data?  Continue Reading

• SQL to calculate days to next status change

  I would like to find out how long a particular customer order has been on hold in SQL.  Continue Reading

• Remove fragmentation of tables and indexes in Oracle

  How to remove fragmentation of tables and indexes in Oracle when tablespaces are in LMT and DMT?  Continue Reading

• Too many reads on inserts

  I have a third-party C++ app running on Oracle 10.2.0.2 and making OCI 9 calls. One of my major problems is that I have a lot of reads on inserts.  Continue Reading

• DBMS JOB Configuration error in RAC system

  I experienced the following error in the database controller for my RAC system: "DBMS JOB Configuration. The Availability calculations for the cluster database target are disabled. Please enable the DBMS JOB EMD_MAINTENANCE.EXECUTE_EM_DBMS_JOB_PROCS...  Continue Reading

• CREATE PUBLIC SYNONYM with EXECUTE IMMEDIATE

  Can we create a PUBLIC SYNONYM in the stored procedure using EXECUTE IMMEDIATE?  Continue Reading

• Hint in view code to force use of index

  I have a view that joins many related tables. The view is quite slow when run wide open. Can I put a hint in the view code to force the use of an index?  Continue Reading

• Is my database using SPFILE or PFILE?

  How do I know whether my database is using SPFILE or PFILE?  Continue Reading

• Oracle performs full table scan in one database

  I have a SQL statement that is behaving differently in two "equal" (in schema) databases. Why the difference in optimizers?  Continue Reading

• How to delete tens of millions of rows from table

  Are there any "best practices" for deleting tens of millions of rows from a table? My understanding is that this could generate a rather large undo file.  Continue Reading

• Migrate cold backup files from HP-UX to Windows

  Is it possible to migrate Oracle 10g cold backup files from HP-UX to Windows?  Continue Reading

• iSQL*Plus won't run on Oracle 9i

  I successfully installed Oracle 9i on my home machine. But when I try to run iSQL*Plus I get the message "Internet Explorer cannot display the webpage."  Continue Reading

• Upgrade Oracle 8.1.7.4 database to Oracle 10.2.0.3 on AIX

  I am planning to upgrade Oracle 8.1.7.4 database to Oracle 10.2.0.3 on AIX 5L system. Please let me know the best way to do this.  Continue Reading

• Oracle 10g fails to create and start Oracle instance

  When I try to install Oracle 10g, in the "creating and starting Oracle instance" stage, an empty menu appears and this phase fails to install. What's the problem?  Continue Reading

• Closing connections to Oracle database takes too long

  Closing connections to my Oracle database takes up to 40 seconds. We have several apps that open a connection, grab some data, then close the connection. However the apps are often timing out because closing the connections take so long.  Continue Reading

• ORA-00204 and ORA-07373 errors during database recovery

  Attempting to recover an Oracle database on a new Unix server, the system returns an ORA-00204 error when trying to start up the databases.  Continue Reading

• Move Oracle home to another partition

  Is it possible to move an Oracle home on Solaris 8 from one partition to another, or is it possible to move an Oracle home to another partition and create a softlink for it in the old partition?  Continue Reading

• How many database instances can be created?

  How many database instances can be created on an Oracle server with an installation drive containing 15 GB free space?  Continue Reading

• Decrypt stored password in Oracle

  How can I decrypt the stored password in Oracle stored in all_users so that I can recover my password any time?  Continue Reading

• Running out of semaphores

  I have a database server with 90+ DB instances. I am having problems creating new databases with the process size greater than 150.  Continue Reading

• Using DBMS_STATS to generate statistics in Oracle 10g

  I need to know the best way to generate statistics within an Oracle 10g database. I read that using dbms_stats is better than using compute command.  Continue Reading

• Errors while trying to restore dropped tablespace

  I took a hot backup with RMAN and am trying to restore a dropped tablespace. I am getting errors including RMAN-06004 and RMAN-20202.  Continue Reading

• Recover database not running in archive log mode

  Some of my system disks crashed. I have reinstalled the operating system and Oracle 9i. Now I want to create a database from existing datafiles and control files. My DB was not running in archive log mode.  Continue Reading

• Does Oracle grid rely on RAC?

  Does Oracle grid computing rely on Real Application Clusters (RAC)?  Continue Reading

• Limit on CLOB datatype in Oracle 10g

  In Oracle 10g, does the 32K limit on the CLOB datatype still apply?  Continue Reading

• ORA-04030: out of process memory when trying to allocate bytes

  When I run a multi-threaded process in Oracle Apps 11i, it fails with the error "ORA-04030: out of process memory when trying to allocate 16396 bytes (koh-kghu sessi,pl/sqlvc2)."  Continue Reading

• Parallel processing causing performance problems

  Our largest tables are defined with "parallel degree nn" in Oracle 9.1. As a consequence, almost all of our queries that run against these tables invoke parallel queries and spawn many, many parallel slaves.  Continue Reading

• ORA-01940: cannot drop a user that is currently connected

  I got an error message while dropping a user: "ORA-01940: cannot drop a user that is currently connected."  Continue Reading

• ORA-03297: file contains used data beyond requested RESIZE value

  I have a datafile that is 16GB. I have moved indexes out and want to shrink the file, but get the error: "ORA-03297: file contains used data beyond requested RESIZE value."  Continue Reading

• ORA-604 and ORA-4021 errors

  We are having some problems that lead me to guess that the ORA-604 at SQL level 1 either causes or is caused by the ORA-4031, and then when the query creating the ORA-604 error at SQL level 2 causes the ORA-4021 lockup and that is when I start ...  Continue Reading

• Why is Oracle 8 an "ORDBMS"?

  Why is Oracle 8 called an ORDBMS?  Continue Reading

• Oracle does not maintain order of inserted records

  I need to have records in table B sorted with regard to the primary key. But Oracle has the problem of not maintaing the order in the way records were inserted.  Continue Reading

• Copy tablespace and dbf files without export

  Is is possible to copy one tablespace and all of its dbf files from one Oracle instance to another Oracle instance without doing an export, just a Unix copy command?  Continue Reading

• Move table without MOVE TABLESPACE command

  I read your answers to questions about moving a table to another tablespace. You said to use ALTER TALBLE....MOVE TABLESPACE. The problem I have is we here still use Oracle 8.1.5 and it doesn't have MOVE TABLESPACE.  Continue Reading

• Getting ORA-12528 error from time to time

  I can connect to the database but I am getting this error: "Failed to connect to database instance: ORA-12528: TNS:listener: all appropriate instances are blocking new connections (DBD ERROR: OCIServerAttach)."  Continue Reading

• Employees with the same first and last names in SQL

  How do I SELECT a list of employees who have the same last and first name in SQL?  Continue Reading

• Import only data, not table structure in Oracle

  Is there a way to import only the data -- not the table structure?  Continue Reading

• "Table or view does not exist" error with DESC command

  On one of the production databases, when I select table_name from dba_tables I get names of 372 tables. But when I use Desc command on most of those tables, I get an error message, "Table or view does not exist."  Continue Reading

• Autoextend vs. adding new datafile

  I have one tablespace which is almost 90% full. Should I autoextend or to add a new datafile?  Continue Reading

• Copying data to new Oracle database with same SID

  I have taken the .dbf, .ctl and .log file from my Oracle database and pasted those files to another Oracle database with the same SID. But it's not working. Am I missing something?  Continue Reading

• Errors during Oracle 10g installation and patch application

  I keep getting errors during the process of installing Oracle 10.2.0.1 and applying the critical patches.  Continue Reading

• ORA-12535 error connecting to local database through VPN

  I have installed Oracle 9.2.0.1 on my local computer. When I try to connect to the installed local database, I get an error: "ORA-12535:TNS operation timed out."  Continue Reading

• ORA-12541 after Oracle 10g Client re-install

  I'm getting "ORA-12541:TNS:no listener" when trying to connect to Oracle in Visual Studio 2005 / SQL Server 2005 Reporting Services. This was not happening until I recently did a re-install of Oracle 10g Client / ODP.Net (via OUI).  Continue Reading

• Install Oracle Forms and Reports on same machine as 9i database

  I have Oracle 9i Database installed on my machine (the OS is Windows XP). I have downloaded Oracle Forms 6i and Oracle Reports 6i on my machine. How can I install them?  Continue Reading

• Home for Oracle Application Server software

  I want to install Oracle Application Server 10g on Linux. What is the recommended home for the Oracle software, and for the database?  Continue Reading

• Using multiple Oracle homes to apply a patch

  How do you use Oracle Enterprise Manager without a database or does this require Opatch from the command line?  Continue Reading

• Upgrade Oracle 8 on Solaris 8 to 10g on Solaris 10

  We are migrating and upgrading our Oracle 8.1.7.4 database on Solaris 8 (64-bit) to a completely new location. The OS will be Solaris 10. The database will be upgraded to 10.2.0.2. What would be the best approach to do that?  Continue Reading

• Migrate Oracle 8i from one server to another

  I want to know the steps to carry out the migration from one Oracle server to another server (same environment). My database is Oracle 8i on Windows 2000.  Continue Reading

• Patch to upgrade to Oracle 10.2.0.3

  I installed Oracle 10.2.0.1 client on Sun Solaris 5.9. Is there any patch to upgrade this 10.2.0.1 to 10.2.0.3?  Continue Reading

• javaw.exe file not found on Oracle Client 9i install

  I am trying to install Oracle Client 9i on a Windows 2003 server. When I run the setup.exe file it gives me an error about the javaw.exe file not being found. We correct that and do not get an error but the client still will not install.  Continue Reading

• Transfer data from Oracle 9i to Oracle 10g

  How to transfer data (tables, indexes, etc.) from Oracle 9i to Oracle 10g?  Continue Reading

• Two SQL homework questions

  In a SQL statement, what is the SELECT clause is used to select? What about the FROM clause?  Continue Reading

• Columns in the SELECT not in the GROUP BY

  I have an SQL query where I am using the SUM function with the GROUP BY clause. I need to select a couple more columns from the table without adding those columns in the GROUP BY clause.  Continue Reading

• Errors installing Oracle Application Server 10g

  I am trying to install Application Server 10g Release 3 (10.1.3.x) on my machine. I am getting the following error when I try to do ./runInstaller.  Continue Reading

• "Failed to request gap sequence" error with switchover

  When I try to do dataguard switchover I get an error message that says "Failed to request gap sequence."  Continue Reading

• Clone Oracle database from Linux to HP-UX

  We need to clone an Oracle database running on Linux to another instance name in a HP-UX box.  Continue Reading

• Oracle Universal Installer doesn't start

  I'm having a problem while trying to install an Oracle 10g database on Windows Server 2003 via Remote Desktop. When I run setup.exe from the CD, the "please wait" command prompt comes up and the Oracle Universal Installer doesn't start.  Continue Reading

• Cannot create Oracle 8.0.5 database on Windows 2003

  Is Oracle 8.0.5 compatible with the Windows 2003 platform running on HP DL 380 G5 5130 2G AP Server?  Continue Reading

• RunInstaller: execute permission denied

  When installing Oracle 10g on an HP-UX machine, it gives an error, "runInstaller: execute permission denied."  Continue Reading

• SQL*Plus not working after Oracle 10g installation

  I have successfully installed Oracle 10g on Linux Enterprise Edition 4 but after that the SQL*Plus command is not working.  Continue Reading

• Steps to migrate from Oracle 8.0.6 to Oracle 10g R2

  I have to migrate from Oracle 8.0.6 to Oracle 10g R2. What are the steps?  Continue Reading

• Can't access iSQL*Plus interface

  I cannot seem to access the iSQL*Plus interface. When I try, the "This page cannot be displayed" error appears. Could this be caused by the fact that I'm using Windows XP Home instead of Pro?  Continue Reading

• Errors with Oracle on Linux installation

  I have installed Oracle 9i on Linux. I created a database on the machine but when I try to start the listener I get TNS errors.  Continue Reading

• When will support for Oracle 9i be discontinued?

  When will general support for Oracle 9i be discontinued?  Continue Reading

• All employees under a given manager

  I want to display all the employees who report to a person. My data is like a tree structure.  Continue Reading

• Can I install Oracle9i on Windows XP?

  Can I install Oracle9i on Windows XP (Home)?  Continue Reading

• Oracle 10g database locking when users log out of ADP software

  Are there any known issues with the Oracle 10g database locking when users log out of ADP software and not allowing them to log back in until a script is run to unlock the database? If so, is there a fix?  Continue Reading

• Easiest way to migrate from Oracle 7i to Oracle 10g

  What is the easiest way to migrate from Oracle 7i to Oracle 10g?  Continue Reading

• How to connect to Oracle 10g server from client machines

  I am able to ping the server from my client machines, but the tnsping shows timeout. How can I connect to the server from the client machines?  Continue Reading

• Oracle Universal Installer throwing error

  I've installed a dual-booting OS running Windows XP and Windows 2000 Server on two partitions. The Oracle Universal Installer is throwing an error.  Continue Reading

• Can't install Oracle 9i on a Windows 2003 Enterprise Edition Server

  I am trying to install Oracle 9i on a Windows 2003 Enterprise Edition Server. When I execute setup.exe, nothing happens.  Continue Reading

• Help finding an entry-level Oracle DBA job

  I am currently a senior and in May 2008 I will have a four-year degree along with an OCA certification. I am currently looking for an entry-level job (related to Oracle) to start gaining (REAL) experience. Unfortunately, my job search to find ...  Continue Reading

• How to restart Oracle 9i database automatically on OS reboot

  On restart of the OS (Solaris 5.10), I need the Oracle 9i database to be restarted automatically.  Continue Reading

• User-managed backup of SYSTEM tablespace

  How to back up a SYSTEM tablespace using a user-managed backup?  Continue Reading

• Simplify backup RMAN script

  I would like to simplify my RMAN script to have a generic one. I need to pass a parameter to the RMAN script (in this case it is a SID for a FORMAT string of the backup statement). Can it be done?  Continue Reading

• Restore a dropped table with hot backup

  I have last night's hot backup. One user unexpectedly dropped a table. How can I restore the table with minimal time?  Continue Reading

• Can't see contents of datafile

  In my Oracle9i database, I made a copy of the existing datafile and created a new tablespace. I am unable to see the contents of the datafile.  Continue Reading

• Running out of space for backups, archive logs

  The Oracle database is growing and the physical disk is out of space. Can I move the archive log folder?  Continue Reading

• Migrate to Oracle on Linux or stick with HPUX?

  We are considering migrating to Linux to reduce hardware costs and also to implement Oracle RAC on two less expensive Linux nodes. Our hardware vendors tell us to stick with HPUX. Where can I get unbiased information on this?  Continue Reading

• Copy data from one schema to a different schema

  I want to copy data from one schema to another for testing purposes. The issue is the two schema are not exactly the same.  Continue Reading

• Generate unique ID based on records in table

  I want to generate the unique ID based on records in the table.  Continue Reading

• SQL query with GROUP BY clause in Oracle 8i vs. Oracle 10g

  I have a SQL query using a GROUP BY clause and no ORDER BY clause. The results are different in Oracle 8i and Oracle 10g.  Continue Reading

• Definition of force view

  What is the force view?  Continue Reading

• Latest three payments for each account in SQL

  I have a table with account_num, payment_date and payment_amt. I only want to display the three latest payments for each account. How do I do this in SQL?  Continue Reading

• Space used by an index in Oracle

  How do I calculate the used space by a INDEX in Oracle?  Continue Reading

• ORA-01017 error when connecting to Oracle XE with SQL*Plus

  I have installed Oracle XE successfully. When I connect on the server, everything works, but when I try to connect from Windows XP client using SQL*Plus, I get the error "ORA-01017: invalid username/password; logon denied."  Continue Reading

• How to practice Oracle 9i on home PC

  I want to practice Oracle at home. I have a single PC with Windows 2000 installed on it. I have got three disks of Oracle 9i version 9.2.0.  Continue Reading