Question 1 :
Why are OPS$ accounts a security risk in a client/server environment? (for DBA)
If you allow people to log in with OPS$ accounts from Windows Workstations, you cannot be sure who they really are. With terminals, you can rely on operating system passwords, with Windows, you cannot.
If you set REMOTE_OS_AUTHENT=TRUE in your init.ora file, Oracle assumes that the remote OS has authenticated the user. If REMOTE_OS_AUTHENT is set to FALSE (recommended), remote users will be unable to connect without a password. IDENTIFIED EXTERNALLY will only be in effect from the local host. Also, if you are using "OPS$" as your prefix, you will be able to log on locally with or without a password, regardless of whether you have identified your ID with a password or defined it to be IDENTIFIED EXTERNALLY.
Question 2 :
Do user parameters appear in the data modal editor in 2.5?
Question 3 :
Can you pass data parameters to forms?
Question 4 :
Is it possible to link two groups inside a cross products after the cross products group has been created?
Question 5 :
What are the different modals of windows?
Question 6 :
What are modal windows?
Modal windows are usually used as dialogs, and have restricted functionality compared to modelless windows. On some platforms for example operators cannot resize, scroll or iconify a modal window.
Question 7 :
What are the different default triggers created when Master Deletes Property is set to Non-isolated?
Master Deletes Property Resulting Triggers
Non-Isolated(the default) On-Check-Delete-Master
Question 8 :
What are the different default triggers created when Master Deletes Property is set to isolated?
Master Deletes Property Resulting Triggers
Question 9 :
What are the different default triggers created when Master Deletes Property is set to Cascade?
Master Deletes Property Resulting Triggers
Question 10 :
What is the diff. bet. setting up of parameters in reports 2.0 reports2.5?
LOVs can be attached to parameters in the reports 2.5 parameter form.
Question 11 :
What are the difference between lov & list item?
Lov is a property where as list item is an item. A list item can have only one column, lov can have one or more columns.
Question 12 :
What is the advantage of the library?
Libraries provide a convenient means of storing client-side program units and sharing them among multiple applications. Once you create a library, you can attach it to any other form, menu, or library modules. When you can call library program units from triggers menu items commands and user named routine, you write in the modules to which you have attach the library. When a library attaches another library, program units in the first library can reference program units in the attached library. Library support dynamic loading-that is library program units are loaded into an application only when needed. This can significantly reduce the run-time memory requirements of applications.
Question 13 :
What is lexical reference? How can it be created?
Lexical reference is place_holder for text that can be embedded in a sql statements. A lexical reference can be created using & before the column or parameter name.
Question 14 :
What is system.coordination_operation?
It represents the coordination causing event that occur on the master block in master-detail relation.
Question 15 :
What is synchronize?
It is a terminal screen with the internal state of the form. It updates the screen display to reflect the information that oracle forms has in its internal representation of the screen.
Question 16 :
What use of command line parameter cmd file?
It is a command line argument that allows you to specify a file that contain a set of arguments for r20run.
Question 17 :
What is a Text_io Package?
It allows you to read and write information to a file in the file system.
Question 18 :
What is forms_DDL?
Issues dynamic Sql statements at run time, including server side pl/SQl and DDL
Question 19 :
How is link tool operation different bet. reports 2 & 2.5?
In Reports 2.0 the link tool has to be selected and then two fields to be linked are selected and the link is automatically created. In 2.5 the first field is selected and the link tool is then used to link the first field to the second field.
Question 20 :
What are the different styles of activation of ole Objects?
In place activationExternal activation
Question 21 :
How do you reference a Parameter?
In Pl/Sql, You can reference and set the values of form parameters using bind variables syntax. Ex. PARAMETER name = '' or :block.item = PARAMETER Parameter name
Question 22 :
What is the difference between object embedding & linking in Oracle forms?
In Oracle forms, Embedded objects become part of the form module, and linked objects are references from a form module to a linked source file.
Question 23 :
Name of the functions used to get/set canvas properties?
Question 24 :
What are the built-ins that are used for setting the LOV properties at runtime?
What are the built-ins used for processing rows?
Question 25 :
What are built-ins used for Processing rows?
Question 26 :
What are the built-in used for getting cell values?
Question 27 :
What are the built-ins used for Getting cell values?
Question 28 :
Atleast how many set of data must a data model have before a data model can be base on it?
Question 29 :
To execute row from being displayed that still use column in the row which property can be used?
Question 30 :
What are different types of modules available in oracle form?
Form module - a collection of objects and code routines Menu modules - a collection of menus and menu item commands that together make up an application menu library module - a collection of user named procedures, functions and packages that can be called from other modules in the application
Question 31 :
What is the remove on exit property?
For a modelless window, it determines whether oracle forms hides the window automatically when the operators navigates to an item in the another window.
Question 32 :
What is WHEN-Database-record trigger?
Fires when oracle forms first marks a record as an insert or an update. The trigger fires as soon as oracle forms determines through validation that the record should be processed by the next post or commit as an insert or update. c generally occurs only when the operators modifies the first item in the record, and after the operator attempts to navigate out of the item.
Question 33 :
What is a difference between pre-select and pre-query?
Fires during the execute query and count query processing after oracle forms constructs the select statement to be issued, but before the statement is actually issued. The pre-query trigger fires just before oracle forms issues the select statement to the database after the operator as define the example records by entering the query criteria in enter query mode.Pre-query trigger fires before pre-select trigger.
Question 34 :
What are built-ins associated with timers?
Question 35 :
What are the built-ins used for finding object ID functions?
Question 36 :
What are the built-ins used for finding Object ID function?
Question 37 :
Any attempt to navigate programmatically to disabled form in a call_form stack is allowed?
Question 38 :
Use the Add_group_row procedure to add a row to a static record group 1. true or false?
Question 39 :
What third party tools can be used with Oracle EBU/ RMAN? (for DBA)
The following Media Management Software Vendors have integrated their media management software packages with Oracle Recovery Manager and Oracle7 Enterprise Backup Utility. The Media Management Vendors will provide first line technical support for the integrated backup/recover solutions.
EMC Data Manager (EDM)
HP OMNIBack II
IBM's Tivoli Storage Manager - formerly ADSM
ManageIT Backup and Recovery
Sterling Software's SAMS:Alexandria - formerly from Spectralogic
Sun Solstice Backup
Question 40 :
Why and when should one tune? (for DBA)
One of the biggest responsibilities of a DBA is to ensure that the Oracle database is tuned properly. The Oracle RDBMS is highly tunable and allows the database to be monitored and adjusted to increase its performance. One should do performance tuning for the following reasons:
The speed of computing might be wasting valuable human time (users waiting for response); Enable your system to keep-up with the speed business is conducted; and Optimize hardware usage to save money (companies are spending millions on hardware). Although this FAQ is not overly concerned with hardware issues, one needs to remember than you cannot tune a Buick into a Ferrari.
Question 41 :
How can a break order be created on a column in an existing group? What are the various sub events a mouse double click event involves?
By dragging the column outside the group.
Question 42 :
What is the use of place holder column? What are the various sub events a mouse double click event involves?
A placeholder column is used to hold calculated values at a specified place rather than allowing is to appear in the actual row where it has to appear.
Question 43 :
What is the use of hidden column? What are the various sub events a mouse double click event involves?
A hidden column is used to when a column has to embed into boilerplate text.
Question 44 :
What database aspects should be monitored? (for DBA)
One should implement a monitoring system to constantly monitor the following aspects of a database. Writing custom scripts, implementing Oracle's Enterprise Manager, or buying a third-party monitoring product can achieve this. If an alarm is triggered, the system should automatically notify the DBA (e-mail, page, etc.) to take appropriate action.
. Is the database up and responding to requests
. Are the listeners up and responding to requests
. Are the Oracle Names and LDAP Servers up and responding to requests
. Are the Web Listeners up and responding to requests
Things that can cause service outages:
. Is the archive log destination filling up?
. Objects getting close to their max extents
. User and process limits reached
Things that can cause bad performance:
See question "What tuning indicators can one use?".
Question 45 :
Where should the tuning effort be directed? (for DBA)
Consider the following areas for tuning. The order in which steps are listed needs to be maintained to prevent tuning side effects. For example, it is no good increasing the buffer cache if you can reduce I/O by rewriting a SQL statement. Database Design (if it's not too late):
Poor system performance usually results from a poor database design. One should generally normalize to the 3NF. Selective denormalization can provide valuable performance improvements. When designing, always keep the "data access path" in mind. Also look at proper data partitioning, data replication, aggregation tables for decision support systems, etc.
Experience showed that approximately 80% of all Oracle system performance problems are resolved by coding optimal SQL. Also consider proper scheduling of batch tasks after peak working hours.
Properly size your database buffers (shared pool, buffer cache, log buffer, etc) by looking at your buffer hit ratios. Pin large objects into memory to prevent frequent reloads.
Disk I/O Tuning:
Database files needs to be properly sized and placed to provide maximum disk subsystem throughput. Also look for frequent disk sorts, full table scans, missing indexes, row chaining, data fragmentation, etc
Eliminate Database Contention:
Study database locks, latches and wait events carefully and eliminate where possible. Tune the Operating System:
Monitor and tune operating system CPU, I/O and memory utilization. For more information, read the related Oracle FAQ dealing with your specific operating system.
Question 46 :
What are the various sub events a mouse double click event involves? What are the various sub events a mouse double click event involves?
Double clicking the mouse consists of the mouse down, mouse up, mouse click, mouse down & mouse up events.
Question 47 :
What are the default parameter that appear at run time in the parameter screen? What are the various sub events a mouse double click event involves?
Destype and Desname.
Question 48 :
What are the built-ins used for Creating and deleting groups?
Question 49 :
What are different types of canvas views?
Content canvas views
Stacked canvas views
Question 50 :
What are the different types of Delete details we can establish in Master-Details?
Question 51 :
What is relation between the window and canvas views?
Canvas views are the back ground objects on which you place the interface items (Text items), check boxes, radio groups etc.,) and boilerplate objects (boxes, lines, images etc.,) that operators interact with us they run your form . Each canvas views displayed in a window.
Question 52 :
What is a User_exit?
Calls the user exit named in the user_exit_string. Invokes a 3Gl program by name which has been properly linked into your current oracle forms executable.
Question 53 :
How is it possible to select generate a select set for the query in the query property sheet?
By using the tables/columns button and then specifying the table and the column names.
Question 54 :
How can values be passed bet. precompiler exits & Oracle call interface?
By using the statement EXECIAFGET & EXECIAFPUT.
Question 55 :
How can a square be drawn in the layout editor of the report writer?
By using the rectangle tool while pressing the (Constraint) key.
Question 56 :
How can a text file be attached to a report while creating in the report writer?
By using the link file property in the layout boiler plate property sheet.
Question 57 :
How can I message to passed to the user from reports?
By using SRW.MESSAGE function.
Question 58 :
Does one need to drop/ truncate objects before importing? (for DBA)
Before one import rows into already populated tables, one needs to truncate or drop these tables to get rid of the old data. If not, the new data will be appended to the existing tables. One must always DROP existing Sequences before re-importing. If the sequences are not dropped, they will generate numbers inconsistent with the rest of the database. Note: It is also advisable to drop indexes before importing to speed up the import process. Indexes can easily be recreated after the data was successfully imported.
Question 59 :
How can a button be used in a report to give a drill down facility?
By setting the action associated with button to Execute pl/sql option and using the SRW.Run_report function.
Question 60 :
Can one import/export between different versions of Oracle? (for DBA)
Different versions of the import utility is upwards compatible. This means that one can take an export file created from an old export version, and import it using a later version of the import utility. This is quite an effective way of upgrading a database from one release of Oracle to the next.
Oracle also ships some previous catexpX.sql scripts that can be executed as user SYS enabling older imp/exp versions to work (for backwards compatibility). For example, one can run $ORACLE_HOME/rdbms/admin/catexp7.sql on an Oracle 8 database to allow the Oracle 7.3 exp/imp utilities to run against an Oracle 8 database.
Question 61 :
What are different types of images?
Boiler plate imagesImage Items
Question 62 :
Can one export to multiple files?/ Can one beat the Unix 2 Gig limit? (for DBA)
From Oracle8i, the export utility supports multiple output files. This feature enables large exports to be divided into files whose sizes will not exceed any operating system limits (FILESIZE= parameter). When importing from multi-file export you must provide the same filenames in the same sequence in the FILE= parameter. Look at this example:
exp SCOTT/TIGER FILE=D:\F1.dmp,E:\F2.dmp FILESIZE=10m LOG=scott.log
Use the following technique if you use an Oracle version prior to 8i:
Create a compressed export on the fly. Depending on the type of data, you probably can export up to 10 gigabytes to a single file. This example uses gzip. It offers the best compression I know of, but you can also substitute it with zip, compress or whatever.
# create a named pipe
mknod exp.pipe p
# read the pipe - output to zip file in the background
gzip < exp.pipe > scott.exp.gz &
# feed the pipe
exp userid=scott/tiger file=exp.pipe ...
Question 63 :
What is bind reference and how can it be created?
Bind reference are used to replace the single value in sql, pl/sql statements a bind reference can be created using a (:) before a column or a parameter name.
Question 64 :
How can one improve Import/ Export performance? (for DBA)
. Set the BUFFER parameter to a high value (e.g. 2M)
. Set the RECORDLENGTH parameter to a high value (e.g. 64K)
. Stop unnecessary applications to free-up resources for your job.
. If you run multiple export sessions, ensure they write to different physical disks.
. DO NOT export to an NFS mounted filesystem. It will take forever.
. Create an indexfile so that you can create indexes AFTER you have imported data. Do this by setting INDEXFILE to a filename and then import. No data will be imported but a file containing index definitions will be created. You must edit this file afterwards and supply the passwords for the schemas on all CONNECT statements.
. Place the file to be imported on a separate physical disk from the oracle data files
. Increase DB_CACHE_SIZE (DB_BLOCK_BUFFERS prior to 9i) considerably in the init$SID.ora file
. Set the LOG_BUFFER to a big value and restart oracle.
. Stop redo log archiving if it is running (ALTER DATABASE NOARCHIVELOG;)
. Create a BIG tablespace with a BIG rollback segment inside. Set all other rollback segments offline (except the SYSTEM rollback segment of course). The rollback segment must be as big as your biggest table (I think?)
. Use COMMIT=N in the import parameter file if you can afford it
. Use ANALYZE=N in the import parameter file to avoid time consuming ANALYZE statements
. Remember to run the indexfile previously created
Question 65 :
Give the sequence of execution of the various report triggers?
Before form , After form , Before report, Between page, After report.
Question 66 :
What are the common Import/ Export problems? (for DBA )
ORA-00001: Unique constraint (...) violated - You are importing duplicate rows. Use IGNORE=NO to skip tables that already exist (imp will give an error if the object is re-created).
ORA-01555: Snapshot too old - Ask your users to STOP working while you are exporting or use parameter CONSISTENT=NO
ORA-01562: Failed to extend rollback segment - Create bigger rollback segments or set parameter COMMIT=Y while importing
IMP-00015: Statement failed ... object already exists... - Use the IGNORE=Y import parameter to ignore these errors, but be careful as you might end up with duplicate rows.
Question 67 :
Why is it preferable to create a fewer no. of queries in the data model?
Because for each query, report has to open a separate cursor and has to rebind, execute and fetch data.
Question 68 :
Where is the external query executed at the client or the server?
At the server.
Question 69 :
Where is a procedure return in an external pl/sql library executed at the client or at the server?
At the client.
Question 70 :
What is coordination Event?
Any event that makes a different record in the master block the current record is a coordination causing event.
Question 71 :
What is the difference between OLE Server & Ole Container?
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.
Question 72 :
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.
Question 73 :
What is an LOV?
An LOV is a scrollable popup window that provides the operator with either a single or multi column selection list.
Question 74 :
At what point of report execution is the before Report trigger fired?
After the query is executed but before the report is executed and the records are displayed.
Question 75 :
What are the built -ins used for Modifying a groups structure?
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.
Question 76 :
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.
Question 77 :
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 is mounted.
Question 78 :
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.
Question 79 :
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.
Question 80 :
My database is down and I cannot restore. What now? (for DBA )
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 money!!!
Question 81 :
I've lost my REDOLOG files, how can I get my DB back? (for DBA)
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 = true
Question 82 :
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 object.
Question 83 :
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.
Question 84 :
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)
Question 85 :
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.
Question 86 :
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 tablespace temp;
SQL> alter user rman quota unlimited on tools;
SQL> grant connect, resource, recovery_catalog_owner to rman;
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;
Question 87 :
How can a group in a cross products be visually distinguished from a group that does not form a cross product?
A group that forms part of a cross product will have a thicker border.
Question 88 :
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.
Question 89 :
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 entered value.
Question 90 :
What are three panes that appear in the run time pl/sql interpreter?
1. Source pane.
2. interpreter pane.
3. Navigator pane.
Question 91 :
What are the two panes that Appear in the design time pl/sql interpreter?
1. Source pane.
2. Interpreter pane
Question 92 :
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.
Question 93 :
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.
Question 94 :
What are the default extensions of the files created by menu module?
Question 95 :
What are the default extensions of the files created by forms modules?
.fmb - form module binary
.fmx - form module executable
Question 96 :
To display the page no. for each page on a report what would be the source & logical page no. or & of physical page no.?
& physical page no.
Question 97 :
It is possible to use raw devices as data files and what is the advantages over file. system files ?
Yes. The advantages over file system files. I/O will be improved because Oracle is bye-passing the kernnel which writing into disk. Disk Corruption will be very less.
Question 98 :
What are disadvantages of having raw devices ?
We should depend on export/import utility for backup/recovery (fully reliable) The tar command cannot be used for physical file backup, instead we can use dd command which is less flexible and has limited recoveries.
Question 99 :
What is the significance of having storage clause ?
We can plan the storage for a table as how much initial extents are required, how much can be extended next, how much % should leave free for managing row updations etc.,
Question 100 :
What is the use of INCTYPE option in EXP command ?
Type export should be performed COMPLETE,CUMULATIVE,INCREMENTAL. List the sequence of events when a large transaction that exceeds beyond its optimal value when an entry wraps and causes the rollback segment toexpand into anotion Completes. e. will be written.