Zappi PHP Developer Interview Questions, Process, and Tips

Echo and print are both used to output data in PHP, but echo is slightly faster and can take multiple arguments.

• Echo is a language construct, while print is a function.

• Echo does not return a value, while print returns 1.

• Echo can output multiple strings separated by commas, while print can only output one string.

• Echo is generally preferred for performance reasons.

Array types and functions

• PHP arrays can store multiple values of different types

• Arrays can be indexed numerically or with strings

• Common array functions include count(), sort(), and array_push()

• Example: $fruits = ['apple', 'banana', 'orange'];

GET and POST are HTTP methods used to send data to a server. GET appends data to the URL while POST sends it in the request body.

• GET is used for retrieving data from a server while POST is used for submitting data to a server.

• GET appends data to the URL as query parameters while POST sends it in the request body.

• GET requests can be bookmarked and cached while POST requests cannot.

• GET requests have length restrictions w...read more

JavaScript is a programming language used for client-side scripting, while jQuery is a library built on top of JavaScript.

• JavaScript is a programming language that allows you to create dynamic web content and interact with the user.

• jQuery is a library that simplifies JavaScript programming by providing pre-written functions and methods.

• JavaScript is a core language, while jQuery is a framework built on top of JavaScrip...read more

Sessions and cookies are used to store and retrieve data in web applications.

• Sessions are used to store data on the server side and are identified by a unique session ID.

• Cookies are used to store data on the client side and are stored as small text files.

• Sessions are more secure as the data is stored on the server, while cookies can be manipulated by the client.

• Sessions are typically used to store sensitive information...read more

An index in MySQL is a data structure that improves the speed of data retrieval operations on a database table.

• Indexes are created on one or more columns of a table to allow for faster searching and sorting of data.

• They work by creating a separate data structure that stores the values of the indexed columns in a sorted manner.

• This allows the database engine to quickly locate the desired data without having to scan the ...read more

Functions in MySQL are predefined or user-defined routines that perform specific tasks.

• MySQL functions can be used to manipulate data, perform calculations, and format output.

• There are various types of functions in MySQL, such as string functions, numeric functions, date and time functions, etc.

• Examples of MySQL functions include CONCAT(), SUBSTRING(), COUNT(), AVG(), NOW(), etc.