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Oracle Interview Questions&Answers Part 10

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Where is the external query executed at the client or the server? 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 event. 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. 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...

Oracle Interview Questions&Answers Part 9

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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. Veritas NetBackup EMC Data Manager (EDM) HP OMNIBack II IBM's Tivoli Storage Manager - formerly ADSM Legato Networker ManageIT Backup and Recovery Sterling Software's SAMS:Alexandria - formerly from Spectralogic Sun Solstice Backup 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 ...

Oracle Interview Questions&Answers Part 8

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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. 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. What is system.coordination_operation? It repre...

Oracle Interview Questions&Answers Part 7

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What is the Maximum allowed length of Record group Column? Record group column names cannot exceed 30 characters. Which parameter can be used to set read level consistency across multiple queries? Read only What are the different types of Record Groups? Query Record Groups NonQuery Record Groups State Record Groups From which designation is it preferred to send the output to the printed? Previewer What are difference between post database commit and post-form commit? Post-form commit fires once during the post and commit transactions process, after the database commit occurs. The post-form-commit trigger fires after inserts, updates and deletes have been posted to the database but before the transactions have been finalized in the issuing the command. The post-database-commit trigger fires after oracle forms issues the commit to finalized transactions. What are the different display styles of list items? Pop_listText_listCombo box Which of the above methods is the faster method? p...

Oracle Interview Questions&Answers Part 6

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An open form can not be execute the call_form procedure if you chain of called forms has been initiated by another open form? True Explain about horizontal, Vertical tool bar canvas views? Tool bar canvas views are used to create tool bars for individual windows. Horizontal tool bars are display at the top of a window, just under its menu bar. Vertical Tool bars are displayed along the left side of a window What is the purpose of the product order option in the column property sheet? To specify the order of individual group evaluation in a cross products. What is the use of image_zoom built-in? To manipulate images in image items. How do you reference a parameter indirectly? To indirectly reference a parameter use the NAME IN, COPY 'built-ins to indirectly set and reference the parameters value' Example name_in ('capital parameter my param'), Copy ('SURESH','Parameter my_param') What is a timer? Timer is an "internal time clock" that you c...

Oracle Interview Questions&Answers Part 5

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What is SGA? The System Global Area in an Oracle database is the area in memory to facilitate the transfer of information between users. It holds the most recently requested structural information between users. It holds the most recently requested structural information about the database. The structure is database buffers, dictionary cache, redo log buffer and shared pool area. What is a shared pool? The data dictionary cache is stored in an area in SGA called the shared pool. This will allow sharing of parsed SQL statements among concurrent users. What is mean by Program Global Area (PGA)? It is area in memory that is used by a single Oracle user process. What is a data segment? Data segment are the physical areas within a database block in which the data associated with tables and clusters are stored. What are the factors causing the reparsing of SQL statements in SGA? Due to insufficient shared pool size. Monitor the ratio of the reloads takes place while executing SQL statem...

Oracle Interview Questions&Answers Part 4

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How does one see the uptime for a database? (for DBA ) Look at the following SQL query: SELECT to_char (startup_time,'DD-MON-YYYY HH24: MI: SS') "DB Startup Time" FROM sys.v_$instance; Marco Bergman provided the following alternative solution: SELECT to_char (logon_time,'Dy dd Mon HH24: MI: SS') "DB Startup Time" FROM sys.v_$session WHERE Sid=1 /* this is pmon */ / Users still running on Oracle 7 can try one of the following queries: Column STARTED format a18 head 'STARTUP TIME' Select C.INSTANCE, to_date (JUL.VALUE, 'J') || to_char (floor (SEC.VALUE/3600), '09') || ':' -- || Substr (to_char (mod (SEC.VALUE/60, 60), '09'), 2, 2) || Substr (to_char (floor (mod (SEC.VALUE/60, 60)), '09'), 2, 2) || '.' || Substr (to_char (mod (SEC.VALUE, 60), '09'), 2, 2) STARTED from SYS.V_$INSTANCE JUL, SYS.V_$INSTANCE SEC, SYS.V_$THREAD C Where JUL.KEY like '%JULIAN%' and SEC.KEY like '%...

Oracle Interview Questions&Answers Part 3

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Define Transaction ? A Transaction is a logical unit of work that comprises one or more SQL statements executed by a single user. What is Read-Only Transaction ? A Read-Only transaction ensures that the results of each query executed in the transaction are consistant with respect to the same point in time. What is a deadlock ? Explain . Two processes waiting to update the rows of a table which are locked by the other process then deadlock arises. In a database environment this will often happen because of not issuing proper row lock commands. Poor design of front-end application may cause this situation and the performance of server will reduce drastically. These locks will be released automatically when a commit/rollback operation performed or any one of this processes being killed externally. What is a Schema ? The set of objects owned by user account is called the schema. What is a cluster Key ? The related columns of the tables are called the cluster key. The cluste...

Oracle Interview Questions&Answers Part 2

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Can a view based on another view? Yes. What are the advantages of views? - Provide an additional level of table security, by restricting access to a predetermined set of rows and columns of a table. - Hide data complexity. - Simplify commands for the user. - Present the data in a different perspective from that of the base table. - Store complex queries. What is an Oracle sequence? A sequence generates a serial list of unique numbers for numerical columns of a database's tables. What is a synonym? A synonym is an alias for a table, view, sequence or program unit. What are the types of synonyms? There are two types of synonyms private and public. What is a private synonym? Only its owner can access a private synonym. What is a public synonym? Any database user can access a public synonym. What are synonyms used for? - Mask the real name and owner of an object. - Provide public access to an object - Provide location transparency for tables, views or program units of a remote dat...

Oracle Interview Questions&Answers Part 1

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What are the components of physical database structure of Oracle database? Oracle database is comprised of three types of files. One or more datafiles, two are more redo log files, and one or more control files. What are the components of logical database structure of Oracle database? There are tablespaces and database's schema objects. What is a tablespace? A database is divided into Logical Storage Unit called tablespaces. A tablespace is used to grouped related logical structures together. What is SYSTEM tablespace and when is it created? Every Oracle database contains a tablespace named SYSTEM, which is automatically created when the database is created. The SYSTEM tablespace always contains the data dictionary tables for the entire database. Explain the relationship among database, tablespace and data file ? Each databases logically divided into one or more tablespaces one or more data files are explicitly created for each tablespace. What is schema? A schema is ...