Oracle Interview Questions and Answers
Where is the external query executed at the client or
At the server.
Where is a procedure return in an external pl/sql
library executed at the client or at the server?
At the client.
What is coordination Event?
Any event that makes a different record in the master
block the current record is a coordination causing
What is the difference between OLE Server & Ole
An Ole server application creates ole Objects that are
embedded or linked in ole Containers ex. Ole servers are
ms_word & ms_excel. OLE containers provide a place to
store, display and manipulate objects that are created
by ole server applications. Ex. oracle forms is an
example of an ole Container.
What is an object group?
An object group is a container for a group of
objects; you define an object group when you want to
package related objects, so that you copy or reference
them in other modules.
What is an LOV?
An LOV is a scrollable popup window that provides the
operator with either a single or multi column selection
At what point of report execution is the before Report
After the query is executed but before the report is
executed and the records are displayed.
What are the built -ins used for Modifying a groups
What is an user exit used for?
A way in which to pass control (and possibly arguments )
form Oracle report to another Oracle products of 3 GL
and then return control ( and ) back to Oracle reports.
What is the User-Named Editor?
A user named editor has the same text editing
functionality as the default editor, but, because it is
a named object, you can specify editor attributes such
as windows display size, position, and title.
My database was terminated while in BACKUP MODE, do I
need to recover? (for DBA)
If a database was terminated while one of its
tablespaces was in BACKUP MODE (ALTER TABLESPACE xyz
BEGIN BACKUP;), it will tell you that media recovery is
required when you try to restart the database. The DBA
is then required to recover the database and apply all
archived logs to the database. However, from Oracle7.2,
you can simply take the individual datafiles out of
backup mode and restart the database.
ALTER DATABASE DATAFILE '/path/filename' END BACKUP;
One can select from V$BACKUP to see which datafiles are
in backup mode. This normally saves a significant amount
of database down time.
Thiru Vadivelu contributed the following:
From Oracle9i onwards, the following command can be used
to take all of the datafiles out of hot backup mode:
ALTER DATABASE END BACKUP;
The above commands need to be issued when the database
What is a Static Record Group?
A static record group is not associated with a query,
rather, you define its structure and row values at
design time, and they remain fixed at runtime.
What is a record group?
A record group is an internal Oracle Forms that
structure that has a column/row framework similar to a
database table. However, unlike database tables, record
groups are separate objects that belong to the form
module which they are defined.
My database is down and I cannot restore. What now? (for
Recovery without any backup is normally not supported,
however, Oracle Consulting can sometimes extract data
from an offline database using a utility called DUL
(Disk UnLoad). This utility reads data in the data files
and unloads it into SQL*Loader or export dump files. DUL
does not care about rollback segments, corrupted blocks,
etc, and can thus not guarantee that the data is not
logically corrupt. It is intended as an absolute last
resort and will most likely cost your company a lot of
I've lost my REDOLOG files, how can I get my DB back?
The following INIT.ORA parameter may be required if your
current redo logs are corrupted or blown away. Caution
is advised when enabling this parameter as you might
end-up losing your entire database. Please contact
Oracle Support before using it. _allow_resetlogs_corruption
What is a property clause?
A property clause is a named object that contains a list
of properties and their settings. Once you create a
property clause you can base other object on it. An
object based on a property can inherit the setting of
any property in the clause that makes sense for that
What is a physical page ? & What is a logical page ?
A physical page is a size of a page. That is output by
the printer. The logical page is the size of one page of
the actual report as seen in the Previewer.
I've lost some Rollback Segments, how can I get my DB
back? (for DBA)
Re-start your database with the following INIT.ORA
parameter if one of your rollback segments is corrupted.
You can then drop the corrupted rollback segments and
create it from scratch.
Caution is advised when enabling this parameter, as
uncommitted transactions will be marked as committed.
One can very well end up with lost or inconsistent
data!!! Please contact Oracle Support before using it. _Corrupted_rollback_segments
= (rbs01, rbs01, rbs03, rbs04)
What are the differences between EBU and RMAN? (for DBA)
Enterprise Backup Utility (EBU) is a functionally rich,
high performance interface for backing up Oracle7
databases. It is sometimes referred to as OEBU for
Oracle Enterprise Backup Utility. The Oracle Recovery
Manager (RMAN) utility that ships with Oracle8 and above
is similar to Oracle7's EBU utility. However, there is
no direct upgrade path from EBU to RMAN.
How does one create a RMAN recovery catalog? (for DBA)
Start by creating a database schema (usually called rman).
Assign an appropriate tablespace to it and grant it the
recovery_catalog_owner role. Look at this example:
SQL>create user rman identified by rman;
SQL> alter user rman default tablespace tools temporary
SQL> alter user rman quota unlimited on tools;
SQL> grant connect, resource, recovery_catalog_owner to
Next, log in to rman and create the catalog schema.
Prior to Oracle 8i this was done by running the
catrman.sql script. rman catalog rman/rman
RMAN>create catalog tablespace tools;
You can now continue by registering your databases in
the catalog. Look at this example:
rman catalog rman/rman target backdba/backdba
RMAN> register database;
How can a group in a cross products be visually
distinguished from a group that does not form a cross
A group that forms part of a cross product will have a
What is the frame & repeating frame?
A frame is a holder for a group of fields. A repeating
frame is used to display a set of records when the no.
of records that are to displayed is not known before.
What is a combo box?
A combo box style list item combines the features found
in list and text item. Unlike the pop list or the text
list style list items, the combo box style list item
will both display fixed values and accept one operator
What are three panes that appear in the run time pl/sql
1. Source pane.
2. interpreter pane.
3. Navigator pane.
What are the two panes that Appear in the design time
1. Source pane.
2. Interpreter pane
What are the two ways by which data can be generated for
a parameters list of values?
1. Using static values.
2. Writing select statement.
What are the various methods of performing a calculation
in a report ?
1. Perform the calculation in the SQL statements itself.
2. Use a calculated / summary column in the data model.
What are the default extensions of the files created by
What are the default extensions of the files created by
.fmb - form module binary
.fmx - form module executable
To display the page no. for each page on a report what
would be the source & logical page no. or & of physical
& physical page no.
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