Top Most Drupal Interview Questions Part – 3
1) What is Drupal?
Drupal is an open source Content Management System (CMS) framework written in PHP. It is used to organize, manage and publish content easily. It provides a variety of customization options to users.
2) What are some most commonly used PHP based CMS?
Following are some most commonly used PHP based CMS:
Drupal
Joomla
WordPress
TYPO3
3) Why Drupal is considered a powerful and popular CMS compare to others?
Drupal facilitates users to create multiple content types using content construction kit (cck) without any programming skill. It also allows customizing theme template for each content type. For example you can have page, article, story, slideshow content type.
4) What are system requirements for Drupal installation?
System requirement for Drupal 8:
Web server: Apache, Nginx, or Microsoft IIS
Database: MySQL 5.5.3/MariaDB 5.5.20/Percona Server 5.5.8 or higher with PDO and an InnoDB-compatible primary storage engine, PostgreSQL 9.1.2 or higher with PDO, SQLite 3.6.8 or higher
PHP 5.5.9 or higher
PHP Memory: 60 MB
5) What are the key features of Drupal?
Following are the two key features of Drupal:
Upload Module: It facilitates users to attach different types of files to node types of your liking.
Embedding: It enables to embed media within nodes that are hosted on your websites.
6) What is caching in Drupal?
In Drupal, caching is used to speed up websites using different configuration like page caching, block caching and lifetime for cached pages.
Page Caching: It enables the entire HTML of each page to be stored in the database. It reduces the amount of queries needed.
Block Caching: You can set the cache setting for a block in views, when block created by views.
Minimum cache lifetime: It is the amount of time before the page cache is cleared. On each cron run, page caches are cleared.
Expiration of cached pages: It only applies for an external mechanism, for example, your browser cache or varnish.
7) What is module in Drupal?
A module is a set of codes that extend Drupal features and functionality. Modules are like plugin for your site. It allows you to add different functions to your site such as polls, contact forms and search fields.
Drupal modules:
Core modules: these modules is included with the main download of Drupal, and you can turn on their functionality without installing additional software.
Contributed modules: These modules are downloaded from the Modules download section of drupal.org, and installed within your Drupal installation.
You can also create your own module “CustomModules” using PHP programming, and Drupal’s module API.
8) Write down some modules that are used in Drupal?
Some of the modules recommended are:
Views
Token
Ctools
Quicktabs
Pathauto
9) What are the SEO modules available in Drupal?
Following are some SEO modules available in Drupal:
Pathauto
Meta tags/ Node words
Service Links
Google Analytics
Related Links
Search 404
Site map
URL list
10) What is a sub theme in Drupal?
Sub themes are just like other themes of Drupal but they have a little difference. Sub themes inherit the parent’s theme. There are many sub themes that can be connected to their parents. A sub-theme can be a child of another sub-theme, and it can be branched and organized however you see fit. This is what gives sub-themes great potential.
11) What does PDO mean in Drupal?
PDO stands for PHP Data Object. It is a lean and consistent way to access databases. It facilitates developers to write portable codes easily. PDO is not an abstraction layer. It is more like a data access layer which uses a unified API.
12) What is DRUSH in Drupal?
DRUSH is a command line shell and UNIX scripting interface for Drupal.
13) Can Drupal run on command line?
Yes. Drupal can be run on command line by using DRUSH.
14) What is the reason behind the use of Ctools in Drupal?
Ctools is a set of APIs and tools that make it easier to handle AJAX requests and tell the clients what to do with them.
15) What are the files required for themes and modules in Drupal?
Required files for themes:
style.css, page.tpl.php , template.php, block.tpl.php
Required files for modules:
modulename.info, modulename.module , optional modulename.install
16) What are the render arrays in Drupal?
Render arrays are the basic building blocks in Drupal. They provide you a structured way to programmatically change the content before it is displayed.
17) What are patches in Drupal?
Patches are the files that contain a list of differences between one set of files, and another. You can make changes like addition, deletion in codes though patches. Patches can also be used to make changes to another copy of the original or main file.
18) Is it possible to disable to core required modules through Drupal admin?
No. It is not possible to disable a core required module through Drupal admin.