Description : Consider the following statements regarding relational database model: (a) NULL values can be used to opt a tuple out of enforcement of a foreign key. (b) Suppose that table T has only one candidate key. If Q is in 3NF, then it is ... true. (C) (b) and (c) are true. (D) (a), (b) and (c) are true.
Last Answer : (D) (a), (b) and (c) are true.
Description : ............. is a combination of two of more attributes used as a primary key A) Composite Key B) Alternate Key C) Candidate Key D) Foreign Key
Last Answer : A) Composite Key
Description : Consider the following database table having A, B, C and D as its four attributes and four possible candidate keys (I, II, III and IV) for this table: I: {B} II: {B, C} III: {A, D} IV: {C, D} If ... the database table? (A) I and III only (B) III and IV only (C) II only (D) I only
Last Answer : (C) II only
Description : An attribute that uniquely identifies the rows of a table is known as the ....... key. (1) primary (2) candidate (3) composite (4) foreign
Last Answer : primary
Description : The candidate key is that you choose to identify each row uniquely is called …………….. A) Alternet Key B) Primary Key C) Foreign Key D) None of the above
Last Answer : B) Primary Key
Description : In a relational database model, NULL values can be used for all but which one of the following? (A) To allow duplicate tuples in the table by filling the primary key column(s) with NULL. (B) To ... D) To fill a column in a tuple when that column does not really exist for that particular tuple.
Last Answer : (A) To allow duplicate tuples in the table by filling the primary key column(s) with NULL.
Description : Integrity constraints ensure that changes made to the database by authorized users do not result into loss of data consistency. Which of the following statement(s) is (are) true w.r.t. the examples of integrity constraints? (A) An ... ) and (B) are true; (C) false. (4) (A), (B) and (C) are false.
Last Answer : Answer: 3
Description : A relation R={A,B,C,D,E,F,G} is given with following set of functional dependencies: F={AD→E, BE→F, B→C, AF→G} Which of the following is a candidate key? (A) A (B) AB (C) ABC (D) ABD
Last Answer : Answer: D
Description : A primary key value can be NULL. -Technology
Last Answer : False The primary key of table is used to uniquely identify each and every row in the table. So, its all keys and columns must be defined as NOT NULL.
Description : State true or false i) A candidate key is a minimal super key. ii) A candidate key can also refer to as surrogate key. A) i-true, ii-false B) i-false, ii-true C) i-true, ii-true D) i-false, ii-false
Last Answer : C) i-true, ii-true
Description : Can null keys be entered in cluster index, normal index ?
Last Answer : Yes.
Description : Based on the cardinality ratio and participation ............... associated with a relationship type, choose either the Foreign Key Design, the Cross Referencing Design or Mutual Referencing Design. (A) Entity (B) Constraints (C) Rules (D) Keys
Last Answer : (B) Constraints
Description : The candidate key, which is not used as primary key is called ………….. key. -Technology
Last Answer : The candidate key, which is not used as primary key is calledalternate key.
Description : What is the difference between candidate key, unique key and primary key
Last Answer : Candidate keys are the columns in the table that could be the primary keys and the primary key is the key that has been selected to identify the rows. Unique key is also useful for identifying the distinct rows in the table.)
Description : Which one is correct w.r.t. RDBMS? (1) primary key ⊆ super key ⊆ candidate key (2) primary key ⊆ candidate key ⊆ super key (3) super key ⊆ candidate key ⊆ primary key (4) super key ⊆ primary key ⊆ candidate key
Last Answer : Answer: 2
Description : Define primary key and candidate key.
Last Answer : Primary Key: A primary key is an attribute in Relation that uniquely identifies the rows in relation. A Primary key does not hold NULL values and duplicate values. OR A key which is selected by the ... , Name) can be a candidate key if and only if Name and Rollno individually are not unique.
Description : A key-board has at least: (A) 91 keys (B) 101 keys (C) 111 keys (D) 121 keys
Last Answer : (B) 101 keys
Description : What is the utility of primary key in database? Write distinct features of primary keys. -Technology
Last Answer : The primary key is used to uniquely identify the record in a database. It can be a column or a set of columns in the table.Main features of the primary key are as follows:1. It must contain a unique value for each record of the table.2. It does not contain null values.
Description : Which of the following statements is FALSE about weak entity set ? (A) Weak entities can be deleted automatically when their strong entity is deleted. (B) Weak entity set avoids the data ... weak entity set are not partitioned according to their relationship with tuples in a strong entity set.
Last Answer : (D) Tuples in a weak entity set are not partitioned according to their relationship with tuples in a strong entity set.
Description : Zero sum games are the one in which there are two agents whose actions must alternate and in which the utility values at the end of the game are always the same. a) True b) False
Last Answer : b) False
Description : In Pandas the function used to check for null values in a DataFrame is ..... -Technology
Last Answer : In Pandas the function used to check for null values in a DataFrame isisnull()
Description : How many control keys are there on the key board ?
Last Answer : Usually there are 2 o'clock. In some cases it is 1 o'clock.
Description : Symmetric - key cryptography refers to ______methods in which both the sender and receiver share the same key ( or , less commonly, in which their keys are different but related in an easily computable way): a) Encryption b) Decryption c) Both of above d) None of These
Last Answer : a) Encryption
Description : In MS-Excel, which of the following keys helps you to selects all cells below the current selection, up to the edge of the current data region: a) Ctrl + Shift + Down Arrow Key b) Ctrl + Shift + Right Arrow Key c) Ctrl + Shift + D d) None of These
Last Answer : a) Ctrl + Shift + Down Arrow Key
Description : ________located on the right corner of the keyboard, is a separate set of number keys for quick input of numbers: a) Numeric Keypad b) Arrow Pad c) Symbolic Key Pad d) None of These
Last Answer : a) Numeric Keypad
Description : _________ and _________ saves the publish and subscribe keys that we have generated with the PubNub Admin portal. a) public_key and subscribe_key b) Public-key and subscribe-key c) publickey and subscribekey d) Key_public and key_subscribe
Last Answer : a) public_key and subscribe_key
Description : By clicking which key the PubNub will display public, subscribe, and secret keys. a) Pane b) Demo Keyset c) Portal d) Network
Last Answer : b) Demo Keyset
Description : can we create a null as a key for a map collection ?
Last Answer : Ans. Yes , for Hashtable. Hashtable implements Map interface.
Description : In RDBMS, the constraint that no key attribute (column) may be NULL is referred to as: (A) Referential integrity (B) Multi-valued dependency (C) Entity Integrity (D) Functional dependency
Last Answer : (C) Entity Integrity
Description : Consider the following relation: Works (emp_name, company_name, salary) Here, emp_name is primary key. Consider the following SQL query Select emp_name From Works T where salary>(select avg ( ... 4) Find all employees who earn more than the average salary of all employees of their company.
Last Answer : Find all employees who earn more than the average salary of all employees of their company.
Description : Let pk(R) denotes primary key of relation R. A many-to-one relationship that exists between two relations R1 and R2 can be expressed as follows: (1) pk(R2)→pk(R1) (2) pk(R1)→pk(R2) (3) pk(R2)→R1∩R2 (4) pk(R1)→R1∩R2
Description : Find the false statement: (A) In Modern Cryptography, symmetric key algorithms use same key both for Encryption and Decryption. (B) The Symmetric cipher DES (Data Encryption Standard) was widely used ... and 124 bits. (D) Public key algorithms use two different keys for Encryption and Decryption.
Last Answer : (C) The AES (Advanced Encryption Standard) cryptosystem allows variable key lengths of size 56 bits and 124 bits.
Description : Public key encryption method is a system a. which uses a set of public keys one for each participant in e-Commerce b. in which each person who wants to communicate has two keys; a private key known to him ... him. c. which uses the RSA coding system. d. which is a standard for use in e-Commerce.
Last Answer : b. in which each person who wants to communicate has two keys; a private key known to him only and a public key which is publicized to enable others to send message to him.
Description : Derive the relation between radian and degree. Also find out 1” and 1’ in terms of their respective values in radian.
Last Answer : Derive the relation between radian and degree. Also find out 1” and 1’ in terms of their respective values in radian. (Take π = 3.1416)
Description : A foreign key is a primary key in another table. -Technology
Last Answer : True When a table’s primary key field is added to a related table in order to create the common field which relates two tables, it is called a foreign key in the related table.
Description : Drop Table cannot be used to drop a table referenced by a …………… constraint. A) Local Key B) Primary Key C) Composite Key D) Foreign Key
Last Answer : D) Foreign Key
Description : ey to represent relationship between tables is called (A) Primary key (B) Secondary Key (C) Foreign Key (D) None of these
Last Answer : (C) Foreign Key
Description : Drop Table cannot be used to drop a Table referenced by .................. constraint. (a) Primary key (b) Sub key (c) Super key (d) Foreign key (A) (a) (B) (a), (b) and (c) (C) (d) (D) (a) and (d)
Last Answer : (C) (d)
Description : In a Examination a candidate has to score minimum of 24 marks inorder to clear the exam. The maximum that he can score is 40 marks. Identify the Valid Equivalance values if the student clears the exam. A. 22,23,26 B. 21,39,40 C. 29,30,31 D. 0,15,22
Last Answer : C. 29,30,31
Description : A perceptron adds up all the weighted inputs it receives, and if it exceeds a certain value, it outputs a 1, otherwise it just outputs a 0. a) True b) False c) Sometimes – it can also output intermediate values as well d) Can’t say
Last Answer : a) True
Description : What are partial, alternate,, artificial, compound and natural key?
Last Answer : Partial Key: It is a set of attributes that can uniquely identify weak entities and that are related to same owner entity. It is sometime called as Discriminator. Alternate Key: All Candidate ... create a unique identifier for the construct is known as creating a compound key. Natural Key:
Description : In a research on the effect of child-rearing practices on stress-proneness of children in competing school projects, the hypothesis formulated is that child rearing practices do influence stress-proneness'. At ... be rejected. (D) No decision can be taken in respect of the research hypothesis.
Last Answer : (B) The research hypothesis will be accepted.
Description : 59.An ideal transformer has infinite values of primary and secondary inductances. The statement is A. True B. False
Last Answer : B. False
Description : I was born a long time ago and have since grown to be respected amongst my peers. I have 2 younger siblings who also make my family proud. My father, a greatly respected figure, taught us many values to ... story isn't fiction, it is grounded in reality, under most of your feet. Who am I? -Riddles
Last Answer : This answer was deleted by moderators
Description : How to initialize all the key's values in a Python dictionary -Web-Development
Last Answer : answer:
Description : Python : how to find top n keys of a dictionary having largest values -Web-Development
Description : Which of these about a dictionary is false? a) The values of a dictionary can be accessed using keys b) The keys of a dictionary can be accessed using values c) Dictionaries aren’t ordered d) Dictionaries are mutable
Last Answer : b) The keys of a dictionary can be accessed using values
Description : Which of the following interface represents a collection of associated keys and values? A) this B) Eventargs C) params D) IDictionary
Last Answer : Which of the following interface represents a collection of associated keys and values? IDictionary
Description : Pick up the incorrect statement from the following: (A) In Flemish bond, headers and stretchers are laid alternately in the same course (B) In Flemish bond every header in each course lies ... laid in every course (D) In English bond, headers and stretchers are laid in alternate courses
Last Answer : Answer: Option C