Question 1

Question 1Assertion (A): A database can have only one table in MySql.Reasoning (R): If a piece of data is stored in two places in the databases, then storage space is wasted.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

A is false but R is true.ExplanationA 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.

Question 2

Question 2Assertion (A): A database constraint can be added or removed any time in/from the database tables.Reasoning (R): Alter table command is used to change the structure of the table.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

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

Question 3

Question 3Assertion (A): SQL has efficient mechanisms to retrieve data stored in multiple tables in a MySQL database.Reasoning (R): The SQL statement CREATE is used to retrieve data from the tables in a database and is also called query statement.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

A is true but R is false.ExplanationSQL 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.

Question 4

Question 4Assertion (A): The SQL keyword Like is used with wildcards only.Reasoning (R): '_' underscore and "%" per cent are the two wildcard characters used with LIKE clause.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

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

Question 5

Question 5Assertion (A): DISTINCT clause must be used in an SQL statement to eliminate duplicate rows.Reasoning (R): DISTINCT works with numeric data type only.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

A is true but R is false.ExplanationThe 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.

Question 6

Question 6Assertion (A): ORDER BY clause is used to sort the records of a table.Reasoning (R): SQL provides two keywords for sorting in ascending and descending orders, ASC and DESC.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

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

Question 7

Question 7Assertion (A): FLOAT and DOUBLE are data types.Reasoning (R): Both can hold any number up to 23 digits.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

A is true but R is false.ExplanationFLOAT 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.

Question 8

Question 1MySQL is a freely available open-source RDBMS that implements SQL.

Accepted Answer