ORACLE DBA INTERVIEW QUESTIONS AND ANSWERS
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41. Explain database clusters?
Group of tables physically stored together because
they share common column and are often used together is
called clusters
42. Explain what is a lookup
table in database? Where can we use these type of the table?
Lookup tables are like
constraints which hold a value. The content in the lookup tables doesn’t
change often, hence as lookup(reference)
Example :-emp table
Emp are not add on regular bases
hence one can consider the table as a lookup table. As and when need in some
other table the emp information can be fetched base on PK-emp-code.
43. Explain when can hash cluster
used?
Hash clusters are useful in case
where
There is a uniform, even and
predictable no. of key values.
Queries using equality predicates..
The table is NOT growing
constantly, and the keys are rarely updated
44.Expalin what is an oracle
sequence?
A sequence is a database
object created by a user that can be used to generate unique integers. A
typical usage if sequence is to generate primary key values
which are unique for each row.
It is generated and
incremented / decremented by an internal oracle routine. It
can be used by multiple users and for multiple tables
too. A sequence can be used instead of writing an application
code for sequence generating routine
45. What is the Index cluster?
An index cluster uses an
index to maintain data within the cluster. The structure of a cluster
index a normal index does not store NULL key values, and
index cluster can store it.
Cluster index is likely to
be smaller than a normal index because, there is only one entry
for each key value in the cluster index, even if that is repeating
46. Explain do a
“VIEW” contain data?
A view does not contain any
data of its own, but is like a window through which data from other tables can
be viewed and changed
47.Explain what is privilege
auditing ?
Privilege auditing is
auditing of the use of powerful system privileges without regard
to specially named objects
48. What is a trace
file and how it is created?
Each server and
background process can write an associated trace file. When an internal
error is detected by a process or user process, it dumps information
about the error
49 What is statement
auditing ?
Statement auditing is
the auditing of the powerful system privileges without.
Regard to specially name objects
50. What is an auditing?
Monitoring of the user
access to aid in the investigation of database use
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