Tag: accountancy

Questions Related to accountancy

The ______ for binary relationship specifies the number of relationship instance that an entity can participate in. 

  1. Timeware based

  2. Computer based

  3. Liveware based

  4. Selection based


Correct Option: B
Explanation:

Cardinality ratios (computer based) for binary relationship specifies the number of relationship instance that an entity can participate in.

The integrity constraints, specified on ________, must hold in every database state of that schema.

  1. Database

  2. Database relation

  3. Database schema

  4. Database system


Correct Option: C
Explanation:

It is a merit for special consideration. The integrity constraints, specified on database schema, must hold in every database state of that schema.

A special value called ______ is used to represent unknown or not applicable values of attributes in a tuple.

  1. Composite

  2. Multi-valued

  3. Null

  4. Both B and C


Correct Option: C
Explanation:

Each value in a tuple is an indivisible value to imply that it is not divisible into components within the framework of the basic relational model. This implies that composite and multi-valued attributes are not allowed. A special value called Null is used to represent unknown or not applicable values of attributes in a tuple.

While ______ and ________ constraints are specified on individual relation, the _______ constraint is specified between two or more relations.

  1. Key, Entity, Referential Integrity

  2. Entity, Candidate, Referential Integrity

  3. Key, Attribute, Referential Integrity

  4. Candidate, Referential Integrity, Attribute


Correct Option: A
Explanation:

While key and entity constraints are specified on individual relation, the referential integrity constraint is specified between two or more relations. This constraint is specified to maintain consistency among the tuples in such relations.

Every relation that has at least one key by default, which is the combination of all its attributes is called _________ by default, which specifies  uniqueness constraint.

  1. Financial key

  2. Super-key

  3. Attribute key

  4. Candidate key


Correct Option: B
Explanation:

Each data record, which corresponds to a tuple of a relation, in a table must be distinct. Every relation has at least one key by default, which is the combination of all its attributes. This key is called super-key by default.

____________ is defined as that part of super-key from which any attribute cannot be removed without sacrificing the uniqueness constraint.

  1. Super key

  2. Minimal super-key

  3. Candidate key

  4. Attribute key


Correct Option: B
Explanation:

Minimal super-key (also called Key) is defined as that part of super-key from which any attribute cannot be removed without sacrificing the uniqueness constraint.

The minimal super-key is also called ______.

  1. Super key

  2. Key

  3. Candidate key

  4. Both A and B


Correct Option: B
Explanation:

Minimal super-key is also called as Key. It is defined as that part of super-key from which any attribute cannot be removed without sacrificing the uniqueness constraint.

___________ operation is carried out to remove a tuple from a relation.

  1. Modify

  2. Delete

  3. Update

  4. Insert


Correct Option: B
Explanation:

There are three basic types of updates: insert, delete and modify. Delete operation is carried out to remove a tuple from a relation. A particular data record from a table can be removed by performing such a operation. The delete operation can violate only referential integrity, if tuple being removed is referenced by foreign key from tuples in the database.

_______ operation on Relational Data Model does not cause violation any integrity constraints.

  1. Retrieval

  2. Updates

  3. Data processing

  4. None of the above


Correct Option: A
Explanation:

There are two categories of operations on relational model: updates and retrieval operation on Relational Data Model does not cause violation any integrity constraints. 

Which of the following are the constraints of database schemas?
a. Domain constraints, Key constraints, Entity integrity constraints, Referential integrity constraints
b. Domain constraints, Data constraints, Entity integrity constraints, Referential integrity constraints

  1. Only "a"

  2. Only "b"

  3. Both "a" and "b"

  4. None of the above


Correct Option: A
Explanation:

A relational database schema is a set of relation schemas and a set of integrity constraints. There are four different constraints, which can be specified on relational database. These are: domain constraints, key constraints, entity integrity constraints, referential integrity constraints.