{"id":550,"date":"2021-12-26T22:14:40","date_gmt":"2021-12-26T22:14:40","guid":{"rendered":"https:\/\/zerotobyte.com\/?p=550"},"modified":"2021-12-26T22:54:08","modified_gmt":"2021-12-26T22:54:08","slug":"an-introduction-to-django-datetimefield","status":"publish","type":"post","link":"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/","title":{"rendered":"An Introduction to Django DateTimeField"},"content":{"rendered":"\n<p>In this Django DateTimeField guide, <strong>we will go through the basics of DateTimeField, use cases, and a couple of practical examples<\/strong>. After this blog post, you will be able to use DateTimeField successfully and with understanding, regardless of the problems, you may encounter when working with dates and times.<\/p>\n\n\n\n<p>To better understand DateTimeField we will answer several questions:<\/p>\n\n\n\n<ul><li><strong>What are accepted DateTimeField inputs?<\/strong><\/li><li><strong>How does DateTimeField save into the database?<\/strong><\/li><li><strong>Why do we use DateTimeField?<\/strong><\/li><\/ul>\n\n\n\n<p>And one practical example:<\/p>\n\n\n\n<ul><li><strong>Adding DateTimeField to model<\/strong><\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Django DateTimeField and its parameters<\/h2>\n\n\n\n<p>All Django field model fields belong to the Field class and represent one column in the database, the same way Datetimefield works.<\/p>\n\n\n\n<p>So what does DateTimeField represent in Django?<br><strong>Django DateTimeField represents the timestamp with timezone in the database. That means it displays the date and time in one of the default formats (unless otherwise stated). <\/strong>Of course, the format of saving the DateTimeField can be changed, which we will show in one of the examples.<\/p>\n\n\n\n<p><code class=\"inline-code-style\">class DateTimeField(auto_now=False, auto_now_add=False, **options)<\/code><\/p>\n\n\n\n<p><strong>DateTimeField in Django has two optional parameters.<\/strong><\/p>\n\n\n\n<ul><li><code class=\"inline-code-style\">auto_now_add<\/code> saves instance of date-time into the database when the object is created.<\/li><li><code class=\"inline-code-style\">auto_now<\/code> saves instance of date-time into the database when the object is saved.<\/li><\/ul>\n\n\n\n<p>Quite often, the <code class=\"inline-code-style\">default<\/code> parameter is used with DateTimeField.<\/p>\n\n\n\n<p><code class=\"inline-code-style\">datetime = models.DateTimeField (default = datetime.now, blank = True)<\/code><\/p>\n\n\n\n<pre class=\"wp-block-verse\"><strong>NOTE<\/strong> - We do not call the datetime.now function (because the function's return value is returned to the default). We only give a reference to the function object so that function can be called when creating a new instance.<\/pre>\n\n\n\n<p>We will best understand DateTimeField if we look at a couple of examples.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Example &#8211; Adding DateTimeField to a model<\/h2>\n\n\n\n<p>I&#8217;ll use a Book model with the <strong>title<\/strong> as a CharField and <strong>published_date<\/strong> as DateTimeField.<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">from django.db import models\n\nclass Book(models.Model):\n    title = models.CharField(max_length=512)\n    published_date = models.DateTimeField()\n<\/pre>\n\n\n\n<p>After applying <a href=\"https:\/\/zerotobyte.com\/django-migrations-explained-through-examples\/\" target=\"_blank\" rel=\"noreferrer noopener\">migrations<\/a>, data will look like this.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td><strong>Name<\/strong><\/td><td><strong>Data Type<\/strong><\/td><td><strong>Database Example<\/strong><\/td><\/tr><tr><td>id<\/td><td>bigint<\/td><td>1<\/td><\/tr><tr><td>title<\/td><td>character varying<\/td><td>Django basics<\/td><\/tr><tr><td>published_datetime<\/td><td>timestamp with time zone<\/td><td>2021-12-31 15:25:00+01<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">DateTimeField Input formats?<\/h2>\n\n\n\n<p>To add DateTime to the database, we need to know all the accepted formats. If we do not use a standard format, a ValidationError will be reported.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td><strong>Format<\/strong><\/td><td><strong>Example<\/strong><\/td><\/tr><tr><td><code class=\"inline-code-style\">%Y-%m-%d %H:%M:%S<\/code><\/td><td>2021-12-12 11:44:59<\/td><\/tr><tr><td><code class=\"inline-code-style\">%Y-%m-%d %H:%M:%S.%f<\/code><\/td><td>2021-12-12 11:44:59.000200<\/td><\/tr><tr><td><code class=\"inline-code-style\">%Y-%m-%d %H:%M<\/code><\/td><td>2021-12-12 11:44<\/td><\/tr><tr><td><code class=\"inline-code-style\">%m\/%d\/%Y %H:%M:%S<\/code><\/td><td>12\/22\/2021 11:44:59<\/td><\/tr><tr><td><code class=\"inline-code-style\">%m\/%d\/%Y %H:%M:%S.%f<\/code><\/td><td>12\/22\/2021 11:44:59.000200<\/td><\/tr><tr><td><code class=\"inline-code-style\">%m\/%d\/%Y %H:%M<\/code><\/td><td>12\/22\/2021 11:44<\/td><\/tr><tr><td><code class=\"inline-code-style\">%m\/%d\/%y %H:%M:%S<\/code><\/td><td>12\/22\/21 11:44:59<\/td><\/tr><tr><td><code class=\"inline-code-style\">%m\/%d\/%y %H:%M:%S.%f<\/code><\/td><td>12\/22\/21 11:44:59.000200<\/td><\/tr><tr><td><code class=\"inline-code-style\">%m\/%d\/%y %H:%M<\/code><\/td><td>12\/22\/21 11:44<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">DateTimeField with Django ORM<\/h2>\n\n\n\n<p>We want to manage each attribute of the model for a variety of reasons, be it some calculations or something else. This is helped by the built-in Django ORM (Object-relational mapping). <strong>Django ORM sets specific built-in methods over the model by which we perform queries on the database in a user-friendly way.<\/strong><\/p>\n\n\n\n<p>So how does Django ORM behave with DateTimeField?<\/p>\n\n\n\n<p>Using the filter method, I will show the methods we can use over the published_date attribute from the above book model.<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># Filters books using the datetime object\nBook.objects.filter(published_datetime='2021-12-31 15:25:00+01')\n\n# Filters books that have a newer date than given\nBook.objects.filter(published_datetime__gt='2021-12-31')\n\n# Filters books that have an older date than given\nBook.objects.filter(published_datetime__lt='2021-12-31')\n\n# Filters the books depending on the day, month or year\nBook.objects.filter(published_datetime__day='31')\nBook.objects.filter(published_datetime__month='12')\nBook.objects.filter(published_datetime__year='2021')\n\n# Filters the book depending on the hour, minute, second\nBook.objects.filter(published_datetime__hour=3)\nBook.objects.filter(published_datetime__minute=25)\nBook.objects.filter(published_datetime__second=0)\n\n# Takes an integer value representing the day of the week from 1 (Sunday) to 7 (Saturday).\nBook.objects.filter(published_datetime__week_day=3)\n#Could be used with gte, gt, lte, lt, \u2026\nBook.objects.filter(published_datetime__week_day__lte=2)\n\n# filters books in a given range\nBook.objects.filter(published_datetime__range=('2021-12-12', '2022-12-12'))\n\n# filters books by the given list of datetimes\nBook.objects.filter(published_datetime__in=['2021-12-31 15:25:00+01', '2022-02-01 07:00:00+01'])\n<\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">DateTimeField Tips and Tricks<\/h2>\n\n\n\n<p>As <strong>updated_at<\/strong> and <strong>created_at<\/strong> are often inserted into a particular model to track activity, there is good practice in defining an abstract class containing these two fields.<br>The goal is to create a class that specific models will extend to avoid code duplication.<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"python\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class TimeStampedModel(models.Model):\n    \"\"\"\n    An abstract base class model that provides\n    self-updating 'created_at' and 'updated_at' field\n    \"\"\"\n\n    created_at = models.DateTimeField(default=timezone.now)\n    updated_at = models.DateTimeField(auto_now=True, null=True)\n\n    class Meta:\n        abstract = True\n\n# Simply inherit TimeStampedModel\nclass Book(TimeStampedModel):\n    title = models.CharField(max_length=512)\n<\/pre>\n\n\n\n<p>Book model will have a <strong>title<\/strong>, <strong>created_at<\/strong>, and <strong>updated_at<\/strong> attributes.<\/p>\n\n\n\n<pre class=\"wp-block-verse\"><strong>NOTE<\/strong> - You may notice that created_at instead of auto_now_add = True uses default = timezone.now, they do the same thing for the given example.<\/pre>\n\n\n\n<p>More about Django DateTimeField in official <a href=\"https:\/\/docs.djangoproject.com\/en\/4.0\/ref\/models\/fields\/#django.db.models.DateTimeField\" target=\"_blank\" rel=\"noreferrer noopener\">Django documentation<\/a>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Conclusion<\/h2>\n\n\n\n<p>DateTimeField is a powerful feature for saving dates and times to a database. But because there is no official date format, problems often arise. For that reason,<br>dates and times are often subject to change. Therefore, <strong>it is necessary to read the official Django documentation every time a new version is released.<\/strong><\/p>\n\n\n\n<p>I hope you found this blog post helpful!<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In this Django DateTimeField guide, we will go through the basics of DateTimeField, use cases, and a couple of practical &#8230; <\/p>\n<p class=\"read-more-container\"><a title=\"An Introduction to Django DateTimeField\" class=\"read-more button\" href=\"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/#more-550\" aria-label=\"More on An Introduction to Django DateTimeField\">Read more<\/a><\/p>\n","protected":false},"author":2,"featured_media":580,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[18,8],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v20.4 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>An Introduction to Django DateTimeField - ZeroToByte<\/title>\n<meta name=\"description\" content=\"Are you often using dates and times in Django? Mastering DateTimeField in Django models can help you improve your application. Check it out!\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"An Introduction to Django DateTimeField - ZeroToByte\" \/>\n<meta property=\"og:description\" content=\"Are you often using dates and times in Django? Mastering DateTimeField in Django models can help you improve your application. Check it out!\" \/>\n<meta property=\"og:url\" content=\"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/\" \/>\n<meta property=\"og:site_name\" content=\"ZeroToByte\" \/>\n<meta property=\"article:published_time\" content=\"2021-12-26T22:14:40+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2021-12-26T22:54:08+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/zerotobyte.com\/wp-content\/uploads\/2021\/12\/django-datetimefield-featured-image-1.webp\" \/>\n\t<meta property=\"og:image:width\" content=\"800\" \/>\n\t<meta property=\"og:image:height\" content=\"547\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/webp\" \/>\n<meta name=\"author\" content=\"Manuel Matosevic\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Manuel Matosevic\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"4 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/\",\"url\":\"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/\",\"name\":\"An Introduction to Django DateTimeField - ZeroToByte\",\"isPartOf\":{\"@id\":\"https:\/\/zerotobyte.com\/#website\"},\"datePublished\":\"2021-12-26T22:14:40+00:00\",\"dateModified\":\"2021-12-26T22:54:08+00:00\",\"author\":{\"@id\":\"https:\/\/zerotobyte.com\/#\/schema\/person\/1ff5aa0c2aabf4491b171a0aee7874a3\"},\"description\":\"Are you often using dates and times in Django? Mastering DateTimeField in Django models can help you improve your application. Check it out!\",\"breadcrumb\":{\"@id\":\"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/zerotobyte.com\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"An Introduction to Django DateTimeField\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/zerotobyte.com\/#website\",\"url\":\"https:\/\/zerotobyte.com\/\",\"name\":\"ZeroToByte\",\"description\":\"Become a Better Dev!\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/zerotobyte.com\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"en-US\"},{\"@type\":\"Person\",\"@id\":\"https:\/\/zerotobyte.com\/#\/schema\/person\/1ff5aa0c2aabf4491b171a0aee7874a3\",\"name\":\"Manuel Matosevic\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/zerotobyte.com\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/e1b521f2dc00628f06c0cc77451013b6?s=96&d=mm&r=g\",\"contentUrl\":\"https:\/\/secure.gravatar.com\/avatar\/e1b521f2dc00628f06c0cc77451013b6?s=96&d=mm&r=g\",\"caption\":\"Manuel Matosevic\"},\"sameAs\":[\"http:\/\/zerotobyte.com\"],\"url\":\"https:\/\/zerotobyte.com\/author\/manuelmatosevic\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"An Introduction to Django DateTimeField - ZeroToByte","description":"Are you often using dates and times in Django? Mastering DateTimeField in Django models can help you improve your application. Check it out!","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/","og_locale":"en_US","og_type":"article","og_title":"An Introduction to Django DateTimeField - ZeroToByte","og_description":"Are you often using dates and times in Django? Mastering DateTimeField in Django models can help you improve your application. Check it out!","og_url":"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/","og_site_name":"ZeroToByte","article_published_time":"2021-12-26T22:14:40+00:00","article_modified_time":"2021-12-26T22:54:08+00:00","og_image":[{"width":800,"height":547,"url":"https:\/\/zerotobyte.com\/wp-content\/uploads\/2021\/12\/django-datetimefield-featured-image-1.webp","type":"image\/webp"}],"author":"Manuel Matosevic","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Manuel Matosevic","Est. reading time":"4 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/","url":"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/","name":"An Introduction to Django DateTimeField - ZeroToByte","isPartOf":{"@id":"https:\/\/zerotobyte.com\/#website"},"datePublished":"2021-12-26T22:14:40+00:00","dateModified":"2021-12-26T22:54:08+00:00","author":{"@id":"https:\/\/zerotobyte.com\/#\/schema\/person\/1ff5aa0c2aabf4491b171a0aee7874a3"},"description":"Are you often using dates and times in Django? Mastering DateTimeField in Django models can help you improve your application. Check it out!","breadcrumb":{"@id":"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/zerotobyte.com\/an-introduction-to-django-datetimefield\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/zerotobyte.com\/"},{"@type":"ListItem","position":2,"name":"An Introduction to Django DateTimeField"}]},{"@type":"WebSite","@id":"https:\/\/zerotobyte.com\/#website","url":"https:\/\/zerotobyte.com\/","name":"ZeroToByte","description":"Become a Better Dev!","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/zerotobyte.com\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":"Person","@id":"https:\/\/zerotobyte.com\/#\/schema\/person\/1ff5aa0c2aabf4491b171a0aee7874a3","name":"Manuel Matosevic","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/zerotobyte.com\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/e1b521f2dc00628f06c0cc77451013b6?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/e1b521f2dc00628f06c0cc77451013b6?s=96&d=mm&r=g","caption":"Manuel Matosevic"},"sameAs":["http:\/\/zerotobyte.com"],"url":"https:\/\/zerotobyte.com\/author\/manuelmatosevic\/"}]}},"_links":{"self":[{"href":"https:\/\/zerotobyte.com\/wp-json\/wp\/v2\/posts\/550"}],"collection":[{"href":"https:\/\/zerotobyte.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zerotobyte.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zerotobyte.com\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/zerotobyte.com\/wp-json\/wp\/v2\/comments?post=550"}],"version-history":[{"count":23,"href":"https:\/\/zerotobyte.com\/wp-json\/wp\/v2\/posts\/550\/revisions"}],"predecessor-version":[{"id":576,"href":"https:\/\/zerotobyte.com\/wp-json\/wp\/v2\/posts\/550\/revisions\/576"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/zerotobyte.com\/wp-json\/wp\/v2\/media\/580"}],"wp:attachment":[{"href":"https:\/\/zerotobyte.com\/wp-json\/wp\/v2\/media?parent=550"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zerotobyte.com\/wp-json\/wp\/v2\/categories?post=550"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zerotobyte.com\/wp-json\/wp\/v2\/tags?post=550"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}