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{"id":4557,"date":"2022-08-02T12:16:39","date_gmt":"2022-08-02T12:16:39","guid":{"rendered":"https:\/\/www.wikitechy.com\/interview-questions\/?p=4557"},"modified":"2022-08-02T12:16:39","modified_gmt":"2022-08-02T12:16:39","slug":"what-is-null-in-php","status":"publish","type":"post","link":"https:\/\/www.wikitechy.com\/interview-questions\/php\/what-is-null-in-php\/","title":{"rendered":"What is NULL in PHP ?"},"content":{"rendered":"<ul>\n<li style=\"text-align: justify;\">In PHP null () function is an inbuilt function which is used to find whether a variable is NULL or not.<\/li>\n<li style=\"text-align: justify;\">If it returns True the given variable is null, otherwise it returns False.<\/li>\n<li style=\"text-align: justify;\">If the value of $x is equal to NULL it returns true and it is an identical comparison operator.<\/li>\n<li style=\"text-align: justify;\">In PHP null is a special data type which can have only one value that is NULL.<\/li>\n<li style=\"text-align: justify;\">NULL data type is a variable that has no value assigned to it and then any variable can be empty by setting the value NULL to the variable.<\/li>\n<\/ul>\n<h2 id=\"sample-code\">Sample Code<\/h2>\n<div class=\"code-embed-wrapper\"> <div class=\"code-embed-infos\"> <\/div> <pre class=\"language-php code-embed-pre line-numbers\"  data-start=\"1\" data-line-offset=\"0\"><code class=\"language-php code-embed-code\">&lt;!DOCTYPE html&gt;<br\/>&lt;html&gt;<br\/>&lt;body&gt;<br\/><br\/>&lt;?php<br\/>$apple = 0;<br\/>echo &quot;apple is &quot; . is_null($a) . &quot;&lt;br&gt;&quot;;<br\/><br\/>$orange = null;<br\/>echo &quot;orange is &quot; . is_null($b) . &quot;&lt;br&gt;&quot;;<br\/><br\/>$grape = &quot;null&quot;;<br\/>echo &quot;grape is &quot; . is_null($c) . &quot;&lt;br&gt;&quot;;<br\/><br\/>$watermelon = NULL;<br\/>echo &quot;watermelon is &quot; . is_null($d) . &quot;&lt;br&gt;&quot;;<br\/>?&gt;<br\/><br\/>&lt;\/body&gt;<br\/>&lt;\/html&gt;<\/code><\/pre> <\/div>\n<h2 id=\"output\">Output<\/h2>\n<p><img fetchpriority=\"high\" decoding=\"async\" class=\"alignnone size-full wp-image-4558\" src=\"https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/08\/null-value-in-php.png\" alt=\"\" width=\"1291\" height=\"519\" srcset=\"https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/08\/null-value-in-php.png 1291w, https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/08\/null-value-in-php-300x121.png 300w, https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/08\/null-value-in-php-1024x412.png 1024w, https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/08\/null-value-in-php-768x309.png 768w, https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/08\/null-value-in-php-390x157.png 390w, https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/08\/null-value-in-php-820x330.png 820w, https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/08\/null-value-in-php-1180x474.png 1180w\" sizes=\"(max-width: 1291px) 100vw, 1291px\" \/><\/p>\n","protected":false},"excerpt":{"rendered":"<p>In PHP null () function is an inbuilt function which is used to find whether a variable is NULL or not. If it returns True the given variable is null, otherwise it returns False. If the value of $x is equal to NULL it returns true and it is an identical comparison operator. In PHP [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"passster_activate_protection":false,"passster_protect_child_pages":"","passster_protection_type":"password","passster_password":"","passster_activate_overwrite_defaults":"","passster_headline":"","passster_instruction":"","passster_placeholder":"","passster_button":"","passster_id":"","passster_activate_misc_settings":"","passster_redirect_url":"","passster_hide":"no","passster_area_shortcode":"","gtb_hide_title":false,"gtb_wrap_title":false,"gtb_class_title":"","gtb_remove_headerfooter":false,"footnotes":""},"categories":[8182],"tags":[17710,17712,17719,17711,17722,17718,17721,17709,17716,17717,17713,17720,17714,17715],"class_list":["post-4557","post","type-post","status-publish","format-standard","hentry","category-php","tag-check-object-is-null-in-php","tag-how-to-assign-null-value-in-php","tag-how-to-use-is-null-in-mysql","tag-is-not-null-in-php","tag-is-null-function-in-mysql","tag-is-null-function-in-php","tag-is-null-in-php-mysql","tag-null-in-php","tag-what-is-null-byte-in-php","tag-what-is-null-coalescing-in-php","tag-what-is-null-in-php","tag-what-is-null-in-text","tag-what-is-null-value-in-php","tag-what-is-the-difference-between-null-and-empty-in-php"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v22.6 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>What is NULL in PHP ? 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