Structured Query Language (SQL)

A is false but R is true.

Explanation
A database can have multiple tables. Data redundancy, which occurs when the same data is repeated in multiple places within a database, leads to wastage of storage space. A DBMS eliminates data redundancy by integrating files, ensuring that multiple copies of the same data are not stored.

Both A and R are true but R is not the correct explanation of A.

Explanation
A database constraint can be added or removed from database tables using the ALTER TABLE command, even after the table has already been created. This command is used to modify the structure of a table by altering the definition of its columns.

A is true but R is false.

Explanation
SQL provides efficient mechanisms, such as JOIN operations, to retrieve data from multiple tables in a MySQL database. The SQL statement CREATE is used to create new database objects such as tables, indexes, or views. The SELECT statement is used to retrieve data from tables in a database and is known as a query statement.

Both A and R are true and R is the correct explanation of A.

Explanation
The SQL LIKE keyword allows the use of wildcard characters to perform pattern matching. SQL provides two wildcard characters to use with the LIKE operator: the percent sign (%) which matches any string, and the underscore ("_") which matches any single character.

A is true but R is false.

Explanation
The DISTINCT clause is used to remove duplicate rows from the results of a SELECT statement. It retrieves only unique values for a column in the table. The DISTINCT keyword in SQL can be used with any data type.

Both A and R are true and R is the correct explanation of A.

Explanation
The SQL ORDER BY clause is used to sort the data is ascending or descending order based on one or more columns. This clause sorts the records in ascending order (ASC) by default. To sort the records in descending order, DESC keyword is used.

A is true but R is false.

Explanation
FLOAT and DOUBLE are data types in SQL, used to store decimal numbers. FLOAT can store values with a precision of around 6-7 digits, while DOUBLE can store values with a precision of around 15-16 digits.

DDL

Reason — The DDL (Data Definition Language) commands allow us to perform tasks related to data definition, i.e., related to the structure of the database objects.

DML

Reason — The DML (Data Manipulation Language) commands are used to manipulate data, i.e., records or rows in a table or relation.

Comment

Reason — A comment is a text which is ignored by the SQL compiler and is not executed at all. It is given for documentation purpose only.

Keywords

Reason — A keyword refers to an individual SQL element that has a special meaning in SQL.

Use

Reason — The USE command is used to open the database for use. The syntax for opening database is : USE <database_name>;.

Select

Reason — The SELECT command is used to retrieve a subset of rows or columns from one or more tables present in a database.

Distinct

Reason — The DISTINCT keyword in SQL is used to eliminate duplicate rows from the results of a SELECT statement.

Describe

Reason — To view a table structure, DESCRIBE or DESC command is used. It shows the structure of the table along with the name of the columns, data type of the columns and constraints applied on the columns.

Primary Key

Reason — A primary key is a set of one or more attributes or fields that uniquely identifies a tuple or row in a table. Therefore, it ensures that each row in the table is unique and prevents the entry of duplicate rows.

show databases;

Reason — The SHOW DATABASES; command lists all the databases managed by the MySQL server.

(B), (D) and (E)

Reason — DDL (Data Definition Language) commands are used to create and define tables and other database objects in SQL (Structured Query Language). DDL commands such as CREATE, ALTER, and DROP, are used to create, define, change and delete objects like tables, indexes, views, and constraints.

(S1) : Correct, (S2) : Incorrect

Reason — The CHAR data type provides fixed-length memory storage. It specifies a fixed-length character string. If the input string is shorter, MySQL pads it with spaces to fill the fixed length. If the input string is longer, it is truncated to fit the fixed length.

Distinct

Reason — The DISTINCT keyword is used to display the unique values of the column in MySQL.

;

Reason — The SQL statements always end with semicolon (;).

Desc

Reason — The DESCRIBE or DESC command is used to view a table structure in MySQL.

Alter

Reason — The ALTER TABLE command is used to delete a primary key constraint from the table.

Select Ename, Salary*12 as "Annual Salary" From Emp;

Reason — The AS keyword is used to give an alias to a column or expression in the SELECT statement. In this case, AS "Annual Salary" is used to rename the column Salary*12 to "Annual Salary" in the display result.

All data from the table

Reason — The asterisk symbol (*) is a wildcard character in SQL that retrieves all columns or fields from a table. When used in a SELECT statement, it returns all columns and rows from the specified table.

Reason — In the above code, a new row is inserted into the 'Student' table, values are provided for RollNumber, SName, and SDateofBirth, but not for GUID. Since GUID is not specified, it will take on its default value, which may be NULL if no default value is defined for the column.

4, 20

Reason — FName is a varchar(20) field, which means it can store a variable-length string up to a maximum of 20 characters. Since the value stored in FName is 'Anuj', it will consume 4 character spaces (A-n-u-j). LName is a char(20) field, which means it is a fixed-length string that always occupies 20 character spaces, regardless of the actual length of the string. Since the value stored in LName is 'Batra', it will still consume 20 character spaces, with the remaining 15 characters being padded with spaces.

A candidate key that is not the primary key is called an alternate key.

A relation is a table i.e., data arranged in rows and columns.

The rows of tables (relations) are called tuples.

The columns of tables (relations) are called attributes.

A domain is a pool of values from which the actual values appearing in a given column are drawn.

All attribute combinations inside a relation that can serve as primary key are candidate keys as they are candidates for the primary key position.

A candidate key that is not the primary key is called an alternate key. In other words, any attribute that is a candidate for the primary key, i.e., which is capable of becoming a primary key but is not a primary key, is an alternate key.

SQL (Structured Query Language) is a standard language for accessing and manipulating databases.

The different categories of SQL commands are as follows:

1. Data Definition Language (DDL) Commands
2. Data Manipulation Language (DML) Commands
3. Data Query Language (DQL) command
4. Data Control Language (DCL) commands
5. Transaction Control Language (TCL) Commands

A Database Management System is a general purpose software system that facilitates the process of defining, constructing and manipulating databases for various applications. The database system is used to eliminate the problems of data redundancy and data inconsistency.

Data types are means to identify the type of data and associated operations for handling it. The data types available in MySQL are int, float, date, time, char, varchar etc.

The + operator is used to concatenate two strings in a query result.

To calculate 13 * 15 in SQL, we can use SELECT statement to retrieve rows computed without reference to any table. For example,

mysql> SELECT 13 * 15;

DISTINCT keyword eliminates the redundant data from a query result.

(a)

SELECT * FROM PRODUCT
WHERE prod_id > 100;

(b)

SELECT * FROM PRODUCT
WHERE prod_name = 'Almirah';

(c)

SELECT * FROM PRODUCT
WHERE price BETWEEN 200 AND 500; 

(d)

SELECT prod_name
FROM PRODUCT
WHERE quantity IS NULL;

(e)

SELECT * FROM PRODUCT;

A database is defined as a collection of interrelated data stored together to serve multiple applications.

Mismatched multiple copies of same data is known as data inconsistency.

A primary key is a set of one or more attributes that can uniquely identify tuples within the relation.

All attribute combinations inside a relation that can serve as primary key are candidate keys as they are candidates for the primary key position.

(a) Differences between ALTER and UPDATE statements:

(ii) Differences between DELETE and DROP statements:

(i)

SELECT * FROM STORE;

+--------+-------------------+-------+-----+------+------------+
| ItemNo | Item              | Scode | Qty | Rate | LastBuy    |
+--------+-------------------+-------+-----+------+------------+
|   2001 | Eraser Small      |    22 | 220 |    6 | 2009-01-19 |
|   2002 | Gel Pen Premium   |    21 | 150 |   12 | 2010-02-24 |
|   2003 | Ball Pen 0.25     |    22 |  50 |   25 | 2010-02-01 |
|   2004 | Eraser Big        |    22 | 110 |    8 | 2009-12-02 |
|   2005 | Sharpener Classic |    23 |  60 |    8 | 2009-06-30 |
|   2006 | Gel Pen Classic   |    21 | 250 |   20 | 2009-03-11 |
|   2009 | Ball Pen 0.5      |    21 | 180 |   18 | 2009-11-03 |
+--------+-------------------+-------+-----+------+------------+

(ii)

SELECT ItemNo, Item FROM STORE WHERE Rate > 15;

+--------+-----------------+
| ItemNo | Item            |
+--------+-----------------+
|   2003 | Ball Pen 0.25   |
|   2006 | Gel Pen Classic |
|   2009 | Ball Pen 0.5    |
+--------+-----------------+

(iii)

SELECT * FROM STORE WHERE Scode = 22 OR Qty > 110;

+--------+-----------------+-------+-----+------+------------+
| ItemNo | Item            | Scode | Qty | Rate | LastBuy    |
+--------+-----------------+-------+-----+------+------------+
|   2001 | Eraser Small    |    22 | 220 |    6 | 2009-01-19 |
|   2002 | Gel Pen Premium |    21 | 150 |   12 | 2010-02-24 |
|   2003 | Ball Pen 0.25   |    22 |  50 |   25 | 2010-02-01 |
|   2004 | Eraser Big      |    22 | 110 |    8 | 2009-12-02 |
|   2006 | Gel Pen Classic |    21 | 250 |   20 | 2009-03-11 |
|   2009 | Ball Pen 0.5    |    21 | 180 |   18 | 2009-11-03 |
+--------+-----------------+-------+-----+------+------------+

(iv) SELECT Rate*Qty FROM STORE WHERE Itemno = 2004;

+------------+
| Rate * Qty |
+------------+
|        880 |
+------------+

(i)

SELECT e.Name, d.DependentName
FROM EMPLOYEE e, DEPENDENT d 
WHERE e.EmpID = d.EmpID;

(ii)

SELECT *
FROM EMPLOYEE
WHERE Department = 'PRODUCTION';

(iii)

SELECT e.Name
FROM EMPLOYEE e, DEPENDENT d 
WHERE e.EmpID = d.EmpID AND d.DependentName IS NULL;

(iv)

SELECT Name
FROM EMPLOYEE
WHERE Department = 'SALES' AND EmpID IN (
    SELECT EmpID
    FROM DEPENDENT
    GROUP BY EmpID
    HAVING COUNT(*) = 2
);

(i)

SELECT * 
FROM BOOKS 
WHERE Publishers = 'FIRST PUBL.' AND author_name = 'J. Mukhi';

+---------+-----------+-------------+-------------+--------+---------+-----+
| book_id | Book_name | author_name | Publishers  | Price  | Type    | qty |
+---------+-----------+-------------+-------------+--------+---------+-----+
| p0001   | Genuine   | J. Mukhi    | FIRST PUBL. | 755.00 | Fiction |  24 |
+---------+-----------+-------------+-------------+--------+---------+-----+

(ii)

SELECT SUM(Price) AS TotalCost 
FROM BOOKS 
WHERE Publishers = 'FIRST PUBL.';

+-----------+
| TotalCost |
+-----------+
|   1105.00 |
+-----------+

(iii)

UPDATE BOOKS 
SET Price = Price - (Price * 0.05)
WHERE Publishers = 'EPB';

(iv)

SELECT Book_name, Price 
FROM BOOKS 
WHERE qty > 3;

+-------------------------+--------+
| Book_name               | Price  |
+-------------------------+--------+
| Let us C                | 427.50 |
| Programming with Python | 350.00 |
| Mastering C++           | 156.75 |
| VC++ advance            | 250.00 |
| Genuine                 | 755.00 |
+-------------------------+--------+

(v)

SELECT * 
FROM BOOKS 
WHERE qty > 30;

+---------+---------------+----------------+------------+--------+------+-----+
| book_id | Book_name     | author_name    | Publishers | Price  | Type | qty |
+---------+---------------+----------------+------------+--------+------+-----+
| m0001   | Mastering C++ | K.R. Venugopal | EPB        | 156.75 | Comp |  60 |
| n0002   | VC++ advance  | P. Purohit     | TDH        | 250.00 | Comp |  45 |
+---------+---------------+----------------+------------+--------+------+-----+

(a)

SELECT *
FROM PRODUCTS
WHERE PNAME = 'PC' AND STOCK > 110;

+-------+-------+---------+-------+-------+-------------+----------+
| PCODE | PNAME | COMPANY | PRICE | STOCK | MANUFACTURE | WARRANTY |
+-------+-------+---------+-------+-------+-------------+----------+
| P004  | PC    | COMPAQ  | 38000 |   120 | 2019-06-20  |        2 |
+-------+-------+---------+-------+-------+-------------+----------+

(b)

SELECT DISTINCT COMPANY
FROM PRODUCTS
WHERE WARRANTY > 2;

+---------+
| COMPANY |
+---------+
| BPL     |
| SONY    |
+---------+

(c)

SELECT COMPANY, SUM(PRICE * STOCK) AS StockValue 
FROM PRODUCTS 
WHERE COMPANY = 'BPL';

+---------+------------+
| COMPANY | StockValue |
+---------+------------+
| BPL     |    2000000 |
+---------+------------+

(d)

SELECT * FROM PRODUCTS;

+-------+----------+---------+-------+-------+-------------+----------+
| PCODE | PNAME    | COMPANY | PRICE | STOCK | MANUFACTURE | WARRANTY |
+-------+----------+---------+-------+-------+-------------+----------+
| P001  | TV       | BPL     | 10000 |   200 | 2018-01-12  |        3 |
| P002  | TV       | SONY    | 12000 |   150 | 2017-03-23  |        4 |
| P003  | PC       | LENOVO  | 39000 |   100 | 2018-04-09  |        2 |
| P004  | PC       | COMPAQ  | 38000 |   120 | 2019-06-20  |        2 |
| P005  | HANDYCAM | SONY    | 18000 |   250 | 2017-03-23  |        3 |
+-------+----------+---------+-------+-------+-------------+----------+

(e)

SELECT PNAME 
FROM PRODUCTS 
WHERE DATE_ADD(MANUFACTURE, INTERVAL WARRANTY YEAR) >= CURDATE();

There is no output produced because the warranty of all products has expired.

The Data Definition Language (DDL) part of SQL permits the creation or deletion of database tables. It also defines indices (keys), specifies links between tables, and imposes constraints on tables. DDL contains necessary statements for creating, manipulating, altering, and deleting tables. Data Manipulation Language (DML) is a part of SQL that helps users manipulate data. It contains necessary statements for inserting, updating, and deleting data.

The number of tuples/rows in a relation is called the Cardinality of the relation.

The number of attributes/columns in a relation is called the Degree of the relation.

(a)

SELECT * 
FROM SCHOOLBUS 
WHERE CAPACITY > 70;

+------+--------------+----------+--------------+----------+----------------+---------+
| Rtno | Area_Covered | Capacity | Noofstudents | Distance | Transporter    | Charges |
+------+--------------+----------+--------------+----------+----------------+---------+
|    1 | Vasant Kunj  |      100 |          120 |       10 | Shivam Travels | 3500.00 |
|    2 | Hauz Khas    |       80 |           80 |       10 | Anand Travels  | 3000.00 |
|    4 | Rohini       |      100 |           90 |       35 | Anand Travels  | 5000.00 |
|    7 | Vasundhara   |      100 |          110 |       20 | Yadav Travels  | 3500.00 |
|    9 | Saket        |      120 |          120 |       10 | Speed Travels  | 3500.00 |
|   10 | Janakpuri    |      100 |          100 |       20 | Kisan Tours    | 3500.00 |
+------+--------------+----------+--------------+----------+----------------+---------+

(b)

SELECT AREA_COVERED 
FROM SCHOOLBUS
WHERE DISTANCE > 20 AND CHARGES < 4000;

(c)

SELECT Transporter, SUM(Charges) AS Total_Charges
FROM SCHOOLBUS
GROUP BY Transporter;

+----------------+---------------+
| Transporter    | Total_Charges |
+----------------+---------------+
| Shivam Travels |          3500 |
| Anand Travels  |         12500 |
| Bhalla Travels |          3800 |
| Yadav Travels  |          7500 |
| Speed Travels  |          6700 |
| Kisan Tours    |          3500 |
+----------------+---------------+

(d)

SELECT RTNO, AREA_COVERED, (CHARGES/NOOFSTUDENTS) AS AVERAEG_COST 
FROM SCHOOLBUS;

+------+---------------+--------------+
| RTNO | AREA_COVERED  | AVERAEG_COST |
+------+---------------+--------------+
|    1 | Vasant Kunj   |    29.166667 |
|    2 | Hauz Khas     |    37.500000 |
|    3 | Pitampura     |    81.818182 |
|    4 | Rohini        |    55.555556 |
|    5 | Yamuna Vihar  |    63.333333 |
|    6 | Krishna Nagar |    50.000000 |
|    7 | Vasundhara    |    31.818182 |
|    8 | Paschim Vihar |    80.000000 |
|    9 | Saket         |    29.166667 |
|   10 | Janakpuri     |    35.000000 |
+------+---------------+--------------+

(e)

INSERT INTO SCHOOLBUS 
VALUES(11, "MOTIBAGH", 35, 32, 10, "KISAN TOURS", 3500);

(a)

SELECT * FROM FURNITURE
WHERE PRICE > 10000;

+----+-------------+-------------+-------------+-------+----------+
| NO | ITEM        | TYPE        | DATEOFSTOCK | PRICE | DISCOUNT |
+----+-------------+-------------+-------------+-------+----------+
|  4 | Decent      | OfficeTable | 2002-02-01  | 25000 |       30 |
|  5 | Comfortzone | DoubleBed   | 2002-02-12  | 25000 |       30 |
+----+-------------+-------------+-------------+-------+----------+

(b)

SELECT ITEM, PRICE
FROM FURNITURE
WHERE DISCOUNT BETWEEN 10 AND 20;

+--------------+-------+
| ITEM         | PRICE |
+--------------+-------+
| Pinkfeathers |  7000 |
| Dolphin      |  9500 |
| Donald       |  6500 |
+--------------+-------+

(c)

DELETE FROM FURNITURE WHERE DISCOUNT = 30;

(d)

SELECT PRICE
FROM FURNITURE
WHERE TYPE = 'BabyCot';

+-------+
| PRICE |
+-------+
|  7000 |
|  9500 |
|  6500 |
+-------+

(e)

SELECT DISTINCT Type FROM Furniture;

+-------------+
| Type        |
+-------------+
| DoubleBed   |
| BabyCot     |
| OfficeTable |
+-------------+

(a)

SELECT NAME FROM GRADUATE 
WHERE `RANK` = 1;

+--------+
| NAME   |
+--------+
| KARAN  |
| RAJ    |
| DIVYA  |
| GAURAV |
| VARUN  |
| LIZA   |
| PUJA   |
+--------+

(b)

SELECT NAME
FROM GRADUATE
WHERE AVERAGE > 65;

+--------+
| NAME   |
+--------+
| KARAN  |
| RAJ    |
| GAURAV |
| LIZA   |
+--------+

(c)

SELECT NAME
FROM GRADUATE
WHERE SUBJECT = 'COMPUTER' AND AVERAGE > 60;

+------+
| NAME |
+------+
| LIZA |
+------+

(d)

SELECT name 
FROM GRADUATE;

+--------+
| name   |
+--------+
| KARAN  |
| RAJ    |
| DEEP   |
| DIVYA  |
| GAURAV |
| MANAV  |
| VARUN  |
| LIZA   |
| PUJA   |
| NISHA  |
+--------+

(e)

SELECT * FROM GRADUATE WHERE Subject = "Physics";

+-------+--------+---------+---------+---------+------+
| S.No. | name   | stipend | subject | average | RANK |
+-------+--------+---------+---------+---------+------+
|     1 | KARAN  |     400 | PHYSICS |      68 |    1 |
|     5 | GAURAV |     500 | PHYSICS |      70 |    1 |
|     9 | PUJA   |     500 | PHYSICS |      62 |    1 |
+-------+--------+---------+---------+---------+------+

(f) Since 'RANK' is a reserved keyword in SQL, we encounter an error while running this query. To avoid such errors, we can enclose the column name 'RANK' in backticks to treat it as a literal identifier.

The corrected query is :

SELECT `RANK` FROM GRADUATE;

+------+
| RANK |
+------+
|    1 |
|    1 |
|    2 |
|    1 |
|    1 |
|    2 |
|    1 |
|    1 |
|    1 |
|    2 |
+------+

The degree of a table is 5 and the cardinality of a table is 10.

(i)

CREATE TABLE STUDENT(
    ROLLNO INT(4) PRIMARY KEY,
    SNAME VARCHAR(25) NOT NULL,
    GENDER CHAR(1) NOT NULL,
    DOB DATE NOT NULL,
    FEES INT(4) NOT NULL,
    HOBBY VARCHAR(15)
);

(ii)

ALTER TABLE STUDENT MODIFY SNAME VARCHAR(30);

(iii)

ALTER TABLE STUDENT DROP HOBBY;

(iv)

INSERT INTO STUDENT(ROLLNO, SNAME, GENDER, DOB, FEES, HOBBY)
VALUES (1, 'ANANYA', 'F', '2000-01-01', 5000, 'COOKING');

(i)

SELECT ProductName, Price 
FROM PRODUCT
WHERE Price BETWEEN 50 AND 150;

+-------------+-------+
| ProductName | Price |
+-------------+-------+
| Bath Soap   |    55 |
| Face Wash   |    95 |
| Shampoo     |   120 |
+-------------+-------+

(ii)

SELECT * FROM PRODUCT
WHERE Manufacturer = 'XYZ' OR Manufacturer = 'ABC';

+------+-------------+--------------+-------+----------+
| P_ID | ProductName | Manufacturer | Price | Discount |
+------+-------------+--------------+-------+----------+
| BS01 | Bath Soap   | ABC          |    55 |     NULL |
| FW05 | Face Wash   | ABC          |    45 |        5 |
| FW12 | Face Wash   | XYZ          |    95 |     NULL |
| SH06 | Shampoo     | XYZ          |   120 |       10 |
+------+-------------+--------------+-------+----------+

(iii)

SELECT ProductName, Manufacturer, Price
FROM PRODUCT
WHERE Discount IS NULL;

+---------------+--------------+-------+
| ProductName   | Manufacturer | Price |
+---------------+--------------+-------+
| Bath Soap     | ABC          |    55 |
| Face Wash     | XYZ          |    95 |
| Talcum Powder | LAK          |    40 |
+---------------+--------------+-------+

(iv)

SELECT ProductName, Price
FROM PRODUCT;

+---------------+--------+
| productname   | price  |
+---------------+--------+
| Bath Soap     |  55.00 |
| Face Wash     |  45.00 |
| Face Wash     |  95.00 |
| Shampoo       | 120.00 |
| Talcum Powder |  40.00 |
+---------------+--------+

(v)

SELECT C.ClientName, C.City, P.P_ID, P.ProductName 
FROM PRODUCT P, CLIENT C 
WHERE P.P_ID = C.P_ID AND C.CITY = 'DELHI';

+---------------+-------+------+---------------+
| ClientName    | City  | P_ID | ProductName   |
+---------------+-------+------+---------------+
| Cosmetic Shop | Delhi | TP01 | Talcum Powder |
| Live Life     | Delhi | BS01 | Bath Soap     |
| Pretty Woman  | Delhi | SH06 | Shampoo       |
| Dreams        | Delhi | FW12 | Face Wash     |
+---------------+-------+------+---------------+

(vi) The column used as a Foreign Key is P_ID in the CLIENT table, and it references the P_ID column in the PRODUCT table.

(i)

SELECT NAME
FROM HOSPITAL
WHERE DATOFADM > '1998-01-15';

+--------+
| NAME   |
+--------+
| Arpit  |
| Kareem |
| Ketaki |
| Ankita |
| Zareen |
| Shilpa |
+--------+

(ii)

SELECT NAME
FROM HOSPITAL
WHERE SEX = 'F' AND DEPARTMENT = 'ENT';

+---------+
| NAME    |
+---------+
| Zareena |
| Ketaki  |
+---------+

(iii)

SELECT NAME, DATOFADM
FROM HOSPITAL;

+---------+------------+
| name    | dateofadm  |
+---------+------------+
| Arpit   | 1998-01-21 |
| Zareena | 1997-12-12 |
| Kareem  | 1998-02-19 |
| Arun    | 1998-01-11 |
| Zubin   | 1998-01-12 |
| Ketaki  | 1998-02-24 |
| Ankit   | 1998-02-20 |
| Zareen  | 1998-02-22 |
| Kush    | 1998-01-13 |
| Shilpa  | 1998-02-21 |
+---------+------------+

(iv)

SELECT NAME, CHARGES, AGE
FROM HOSPITAL
WHERE SEX = 'F';

+---------+---------+-----+
| NAME    | CHARGES | AGE |
+---------+---------+-----+
| Zareena |     250 |  22 |
| Ketaki  |     250 |  16 |
| Ankita  |     800 |  29 |
| Zareen  |     300 |  45 |
| Shilpa  |     400 |  23 |
+---------+---------+-----+

True

Reason — Data redundancy refers to the duplication of data in a database.

False

Reason — An attribute (column) is a set of values of similar type of data.

True

Reason — MySQL is a cross-platform database management system that runs on various operating systems, including UNIX and Windows.

False

Reason — CREATE TABLE command is used to create table in a database.

False

Reason — The correct syntax for inserting a NULL value is : INSERT INTO TABLE_NAME VALUES (NULL, NULL, ...); or INSERT INTO TABLE_NAME (COLUMN_NAME) VALUES (NULL);.

True

Reason — The ALTER TABLE command in SQL is used to modify the definition (structure) of a table by modifying the definition of its columns.

False

Reason — Each SQL table must have at least one column, there is no requirement for it to have at least one row.

True

Reason — Foreign key column refers to value of an attribute defined as the primary key in another table.

True

Reason — The DISTINCT keyword in SQL is used to eliminate duplicate rows from the results of the SELECT statement.

False

Reason — A primary key is necessary in a table as it uniquely identifies each record.

True

Reason — A primary key is a candidate key chosen to uniquely identify rows in a table. All primary keys are candidate keys, but not all candidate keys become primary keys, as only one is selected for that role.