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Your "posts" models is like this :

class Posts(models.Model):
    title = models.CharField(max_length=100)
    description = models.TextField(max_length=155)
 	
    class Meta:
        verbose_name_plural = "Posts"

    def __str__(self):
        return self.title		

# values_list()

For example:

Note : You can also pass in a flat parameter if you only pass in a single field, It will either return true/false.

Let's look at an example to make the difference clear:

Output:

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Let's try to create a simple example :

 import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.Scanner;

class FindSpecialCharactetrs {

    public static void main(String args[]) {
        Scanner input = new Scanner(System.in);  
        String str;

        System.out.print("\nEnter a string : ");
        str = input.nextLine(); 

        Pattern string_patterns = Pattern.compile("[^a-z0-9 ]", Pattern.CASE_INSENSITIVE);  
        Matcher string_matcher = string_patterns.matcher(str);  

        System.out.println("\n\n\t______________ OUTPUT ______________");
        System.out.println("\nYour string is : "+str);

        int count = 0;

        while(string_matcher.find()) {
            count = count + 1;
            System.out.println("\tposition "+string_matcher.start() +": "+ str.charAt(string_matcher.start()));
        }

        System.out.println("\nThere are "+count+" special characters");
        System.out.println("\n\t------------------------------------");

    }
}
 

Output 1:

Output 2:

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Let's try to create a simple example :

 import java.util.Scanner;

class FindSpecialCharactetrs {
    public static void main(String args[]) {
        Scanner input = new Scanner(System.in);  
        String str;
        char find_special_charactetr[] = new char[150];  

        System.out.print("\nEnter a string : ");
        str = input.nextLine(); 

        int p, special_charactetr = 0;
        char a[] = str.toCharArray();
        
        int len = a.length;

        for (int i = 0; i < len; i++) {
            p = a[i];
            if (p >= 65 && p <= 90 || p >= 97 && p <= 122 || p == 32 || p >= 48 && p <= 57) {
                continue;
            } else {
                find_special_charactetr[special_charactetr] = a[i];
                special_charactetr++;
            }
        }


        if (special_charactetr > 0) {
            System.out.println("\n\n\t______________ OUTPUT ______________");
            System.out.println("\nSpecial characters is :" + String.valueOf(find_special_charactetr));
            System.out.println("There are " + special_charactetr + " special characters");
            System.out.println("\n\t------------------------------------");
            System.out.println("\n###### Thanks For Visit 'www.coderwebsite.com' aa####### ");
            
        } else {        
            System.out.println("\n\n\t______________ OUTPUT ______________");
            System.out.println("\n Note that : No any special characters in : {"+str+"}");
            System.out.println("\n\t------------------------------------");
            System.out.println("\n###### Thanks For Visit 'www.coderwebsite.com' ####### ");
        }

    }
}

Output 1:

Output 2:

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# Reason

UTF-8 encoding may be two, three, or four bytes, Emoji expressions are 4-bytes, and MySql utf8 encoding is up to 3-bytes, so the data can't be inserted.

# Solution :

Convert Mysql encoding from utf8 to utf8mb4. The detailed description is as follow steps:

# Settings in MySql:

Step 1 : Modify the character set of the database:

Step 2 : Use the database that currently needs character set modification:

Step 3 : Modify the character set of the table:

Step 4 : Modify the character set of the column:

# Settings in django:

Step 5 : And finally, modify the code in settings.py as follows:

# Remove m=1 From URL of Blogger post

Follow the few steps below and removed ?m=1 from the URL of your blogger post.

Step 1 : First, you login into your blogger's dashboard and then select your blog.

Step 2 : Click on the Theme option.

Step 3 : Click on the customise

Step 4 : Click on Edit HTML option.

Step 5 : Press (CTRL + F) from the keyboard and type "/head" and then search. (If you are not understanding, see the below photo)

Step 6 : Now paste the below code just above the </head> tag.

let's see code :

<script type='text/javascript' >
    //<![CDATA[
var uri = window.location.toString();
if (uri.indexOf("%3D","%3D") > 0) {
var clean_uri = uri.substring(0, uri.indexOf("%3D"));
window.history.replaceState({}, document.title, clean_uri);
}
var uri = window.location.toString();
if (uri.indexOf("%3D%3D","%3D%3D") > 0) {
var clean_uri = uri.substring(0, uri.indexOf("%3D%3D"));
window.history.replaceState({}, document.title, clean_uri);
}
var uri = window.location.toString();
if (uri.indexOf("&m=1","&m=1") > 0) {
var clean_uri = uri.substring(0, uri.indexOf("&m=1"));
window.history.replaceState({}, document.title, clean_uri);
}
var uri = window.location.toString();
if (uri.indexOf("?m=1","?m=1") > 0) {
var clean_uri = uri.substring(0, uri.indexOf("?m=1"));
window.history.replaceState({}, document.title, clean_uri);
}
//]]>
</script>

Step 7 : Finally Click on Save icon to save your settings and code.

Just save and go to mobile and check the permalink / URL of your blogger post. You will see that "M = 1" has been removed. Now enjoy without "m=1 or m=0" URL, Happy Blogging :)

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Let's see, How to use a postgres database in Django app :

Step 1 : When you open the pgadmin panel you will view a server icon in the navigation at the left side of the window. Click on it to open the databases icon. Right Click on the databases icon to create a new database and fill the prerequisites for creating the database.

Step 2 : Next we need to install an adapter for connecting our database with the Django App. We will be using "psycopg2" for this purpose.

Step 3 : Now go-to the "settings.py" file of the Django App and Under the settings file for Databases, change the settings from sqlite3 or your current database to the following code.

Step 4 : Now run makemigrations command to convert all the models into queries for the database.

Step 5 : And finally run migrate command to migrate these changes into our database.

Note that: To install psycopg2 adapter, We will also need to install pillow in case we wish to save any pictures in our database. This can be done using. Have fun!

Note : This article related to DEBUG = True , if you have problems with DEBUG = False then you can follow this article; Static files not working when DEGUB= False. Have fun!

Let's follow a few steps and, solve the problem of not loading Django static files:

Step 1 : Check that "BASE_DIR" is defined in your project settings.py , if not then define it

Step 2 : check debug mode in settings.py.

Step 3 : Define a STATIC_URL and STATICFILES_DIRS in settings.py.

Step 4 : In your templates, For access to static files. use the static template tag to build the URL for the given relative path

• Store your static files in a folder called static in your app For example my_app/static/image/example.jpg.

Step 3 : Now finally, you can run your django project.

Note : Congratulations, now static files will be loaded in your Django project!

# Problem:

Django static and media files not working when debug is false

# Problem Fix:

Let's see, How you can fix the problem of Django static and media files not working when DEBUB = False :

1.)First way: devserver in insecure mode

If you still need to server static locally (e.g. for testing without debug) you can run devserver in insecure mode:

--insecure: it means you can run server without security mode.

Note: This is Exactly you must type on terminal to run your project without "DEBUG = TRUE" and then you see all assets (static) file is loading correctly On local server.

2.)Second way: devserver in secure mode

Step 1 : Define a STATIC_ROOT and MEDIA_ROOT path in settings.py.

Step 2 : Now define your URLConf that if static is in the beginning of url, access files from the static folder staticfiles.

Note: This is your project's urls.py file.

Step 3 : Now you can run your django project.

Note : Congratulations, now static and media files will be loaded in your Django project when DEBGU = False. Have fun!

Let's try to create a simple example :

Output :

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1.) STATICFILES_DIRS :

Need to be used in the development mode. Static files are usually placed in two places:

• The static directory under each app.

• The static directory under the project root directory (because some static files are not unique to an app).

STATICFILES_DIRS tells django to first look for static files in STATICFILES_DIRS, and then go to the static folder of each app.

Note : django finds static files as lazy lookups. When you find the first one, it stops looking up.

2.) STATIC_ROOT :

This constant is not used in development mode and will be used during deployment.

Python manage.py collectstatic when deploying, django will copy the static files of all apps to the STATIC_ROOT folder.

3.) STATIC_URL :

Django uses STATIC_URL to give browsers direct access to static files

So if your project root / static / there is a 123.png image.

Then you can go directly through the browserhttp://IP: port number / static / 123.png to access your picture

Cause

Compared to pgAdmin3 included in PostgreSQL database version 9.4.22, pdAdmin4 included in PostgreSQL database version 10.9 is a different client executable file, which could not be executed on Linux platform,

#Solution

To enable launching the new pdAdmin4 client, a startup script was added, which then requires users to run the script in order to access the client.

3 Ways To Connect Django With MongoDB:

1. Djongo.

2. MongoEngine.

3. PyMongo.

1.) Djongo

Dongo is an open-source project and regularly maintained.

Djongo is a smarter approach to pymongo programming. It is an extension to the traditional Django ORM framework. It maps python objects to MongoDB documents, a technique popularly referred to as Object Document Mapping or ODM.

# Let's start connecting "Django" with "MongoDB" using djongo

Step 1 : To set up the environment for Djongo, you first need to install the package.

Step 2 : Now go-to the "settings.py" file of the Django App and Under the settings file for Databases, change the settings from sqlite3 or your current database to the following code.

Step 3 : Now run makemigrations command to convert all the models into queries for the database.

Step 4 : And finally run migrate command to migrate these changes into our database.

Note : Congratulations, your Django project is now connected with MongoDB. Have fun!

Requirements

1. Python 3.6 or higher

2. MongoDB 3.4 or higher

3. If your models use nested queries or sub querysets like this:

Note that: Django does't create a MongoDB database. So you must have a pre-made MongoDB database, if not, then you create a new database in Mongodb, Then Djongo helps to connect to that database and acts as a transpiler from SQL to MongoDB.

2.) MongoEngine

MongoEngine is an ORM (object relation mapping) layer on the top of PyMongo written in python. Using MongoEngine will grant you additional benefits like fields DictFieldand ListField which you will see very useful when dealing with unstructured JSON data in MongoDB.

# Let's start connecting "Django" with "MongoDB" using MongoEngine

Step 1 : To set up the environment for Djongo, you first need to install the package.

Step 2 : After that, open your project "settings.py", and change the DATABASES part to this code.

Requirements

1. MongoDB 3.4, 3.6, 4.0

2. pymongo>=3.4

3. If your models use nested queries or sub querysets like this:

Note that: You do not need to do makemigrations and migrate since you are not using Django ORM here.

3.) PyMongo

PyMongo is a Python distribution containing tools for working with MongoDB, PyMongo is the recommended way to work with MongoDB from Python. It is great for writing and saving JSON data to your MongoDB, and it will let you use all of the mongo queries in your python code.

Installation

Step 2 : After that Installation, create "utils.py" file in your project root directory(project/utils.py) and add these lines.