What command would you use to create a backup control file?
Alter database backup control file to trace. Read more »
Archive for May, 2008
Give two examples of referential integrity constraints?
A primary key and a foreign key. Read more »
Give the reasoning behind using an index?
Faster access to data blocks in a table. Read more »
Compare and contrast TRUNCATE and DELETE for a table?
Both the truncate and delete command have the desired outcome of getting rid of all the rows in a table. The difference between the two is that the truncate command... Read more »
Give two examples of how you might determine the structure of the table DEPT?
Use the describe command or use the dbms_metadata.get_ddl package. Read more »
How do you switch from an init.ora file to a spfile?
Issue the create spfile from pfile command. Read more »
Why use a DTD?
XML provides an application independent way of sharing data. With a DTD, independent groups of people can agree to use a common DTD for interchanging data. Your... Read more »
What is the purpose of XML Namespaces?
An XML Namespace is a collection of element types and attribute names. It consists of 2 parts 1) The first part is the URI used to identify the namespace 2) The... Read more »
Why are recursive relationships bad? How do you resolve them
A recursive relationship (one where a table relates to itself) is bad when it is a hard relationship (i.e. neither side is a “may” both are “must”)... Read more »
What file will give you Oracle instance status information?
The alert.ora log. It is located in the directory specified by the background_dump_dest parameter in the v$parameter table. Read more »
How can you determine if the SQLNET process is running for SQLNET V1? How about V2?
For SQLNET V1 check for the existence of the orasrv process. You can use the command “tcpctl status” to get a full status of the V1 TCPIP server, other... Read more »
How can you determine if an Oracle instance is up from the operating system level?
There are several base Oracle processes that will be running on multi-user operating systems, these will be smon, pmon, dbwr and lgwr. Any answer that has them using... Read more »
When should you consider denormalization?
Whenever performance analysis indicates it would be beneficial to do so without compromising data integrity. Read more »
What is a pseudo column. Give some examples
It is a column that is not an actual column in the table. eg USER, UID, SYSDATE, ROWNUM, ROWID, NULL, AND LEVEL. Suppose customer table is there having different... Read more »
Difference between an implicit & an explicit cursor?
PL/SQL declares a cursor implicitly for all SQL data manipulation statements, including quries that return only one row. However,queries that return more than one... Read more »