Concentrix Corporation Interview Questions and Answers

Null in a table represents a missing or unknown value, while auto increment in MySQL automatically generates unique values for a column.

• Null in a table indicates that a particular field does not have a value assigned to it.

• Auto increment in MySQL is used to automatically generate a unique value for a column, typically for primary keys.

• For example, a column with auto increment in MySQL will automatically assign a unique number to each new row added to the table.

Functions in PHP are blocks of code that can be reused throughout a program. Functions can return values or other functions.

• Functions in PHP are defined using the 'function' keyword followed by the function name and parameters.

• Functions can return a value using the 'return' keyword.

• Functions can also return other functions, known as 'higher-order functions'.

Order By is a clause in SQL used to sort the result set of a query based on specified columns.

• Order By is used to sort the result set in ascending or descending order.

• It is typically used at the end of a SELECT statement.

• Example: SELECT * FROM table_name ORDER BY column_name ASC;

Primary key uniquely identifies each record in a table, while foreign key establishes a link between two tables.

• Primary key ensures data integrity by preventing duplicate records.

• Foreign key establishes a relationship between tables by referencing the primary key of another table.

• Example: In a database of students and courses, student ID can be a primary key in the students table and a foreign key in the courses table.

Tags and elements in HTML are used to structure and format content on a webpage.

• Tags are used to define the structure of content on a webpage.

• Elements are made up of a start tag, content, and an end tag.

• Examples of tags include <p> for paragraphs and <h1> for headings.

To delete a column in a database, you can use the ALTER TABLE command.

• Use the ALTER TABLE command followed by the DROP COLUMN keyword and the name of the column you want to delete.

• Make sure to specify the table name where the column exists.

• Example: ALTER TABLE table_name DROP COLUMN column_name;

To set path in CMD, use the 'set' command followed by the path to the desired directory.

• Open CMD by searching 'cmd' in the start menu

• Use the 'cd' command to navigate to the desired directory

• Use the 'set' command followed by 'PATH=C:\desired\directory' to set the path