The statement
Every foreign-key value must match a primary-key value in an associated table
Is related to
View
Cursor defination
Referential intergrity
Trigger
Correct Answer :
C. Referential intergrity
Related Questions
Which of the following extracts its data from the result of an SQL SELECT statement.
View
Synonym
Sequence
Transaction
Technique(s) used for data recovery after any failure
Logging
Recovery manager
Both A and B are true
Both A and B are false
Benefit of database normalization is
smaller number of tables
higher query processing efficiency
reduced I/O for most queries
reduced data redundancy
The left outer join takes all tuples
in the left relation which didnt match with any tuple in right relation
in the left relation which matched with a tuple in right relation
in the right relation which didnt match with any tuple in left relation
in the right relation which matched with a tuple in left relation
.................. is the loss of energy as the signal propagates outward, where the amount of energy depends on the frequency.
Noise
Delay distortion
Attenuation distortion
Dispersion
For large networks, _______ topology is used
Ring
Bus
Mesh
none of these
Tape storage is referred to as
sequential access storage
direct access storage
random access storage
none of the above
Primary storage
magnetic disk
magnetic tape
juke box
cache
The exists construct returns the value true, if the argument subquery is
empty
nonempty
contains null values
none of the above
Which of the following produces the relation that has attributes of R1 and R2
Cartesian product
Difference
Intersection
Product
A logical schema
is the entire database.
is a standard way of organizing information into accessible parts.
describes how data is actually stored on disk.
both A) and C)
File organization that provides fast access to any arbitrary record
Hashed file
B-tree
Ordered file
Unordered file
Which of the following operator preserves unmatched rows of the relations being joined?
Inner join
Outer join
union
Intersect
In an Entity-Relationship Diagram Diamonds represents
Attributes
Multi-valued attributes
Weak entity set
Relationship sets
A type of query that is placed within a WHERE or HAVING clause of another query is called
Super query
Sub query
Master query
Multi-query
The raw facts and figures are:
Data
Data field
DBMS
DBASE
The minimal set of super key is called
Primary key
Secondary key
Candidate key
Foreign key
Which command is used to cancel privileges granted through the GRANT command ?
CANCEL
OVER
STOP
REVOKE
An association of several structure of a data base can be expressed graphically by?
Tuple
Record
Relationship
Field
............... noise is caused by the random motion of the electrons in a wire and is avoidable.
Thermal
Intermodulation
Cross talk
Impulse
Which of the following normalization is needed, if an attribute of a composite key is dependent on an attribute of the other composite key?
BCNF
Second
Third
Fourth
The types of noiseless channels are
i) Selective Reject ARQ
ii) simplest protocol
iii) Go-Back-N ARQ
iv) Stop-and-Wait Protocol
i, ii only
ii and iv only
ii and iv only
i, iv only
A table that displays data redundancies yields ____________ anomalies
Insertion
Deletion
Update
All of the above
It is possible to define a schema completely using
VDL and DDL.
DDL and DML.
SDL and DDL.
VDL and DML.
The method by which the structure of the database is modified to eliminate hidden dependencies and replacing groups is
Normalization
Indexing
Enforcing referential integrity
Enforcing data integrity
The attribute that can be divided into other attributes is called
Simple Attribute
Composite Attribute
Multi-valued Attribute
Derived Attribute
Select the correct
i) A timestamp-based scheduler cant produce live lock
ii) Aggregate functions cant appear with HAVING clause.
iii) Isolation is a property of database transaction.
i and ii only
ii and iii only
i and iii only
i only
What does a field or a combination of fields that has a unique value called ?
Foreign key
Secondary key
Primary key
Alternate key
The overall design of a database is called
Subschema of the database
Schema of the database
Structure of the database
View of the database
In the architecture of a database system external level is the
physical level.
logical level.
conceptual level
view level.