Try-Catch for Exception Handling

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from flask import Flask
from flask_sqlalchemy import SQLAlchemy
import os

app = Flask(__name__)

# Adjust the DATABASE_URL format for SQLAlchemy compatibility
database_url = os.getenv("DATABASE_URL", "")
if database_url.startswith("postgres://"):
    database_url = database_url.replace("postgres://", "postgresql+psycopg2://")

app.config["SQLALCHEMY_DATABASE_URI"] = database_url

# Initialize the SQLAlchemy object
db = SQLAlchemy(app)

# Sample route to test the setup
@app.route("/")
def index():
    return "Database URI setup complete!"

if __name__ == "__main__":
    app.run()

• This code retrieves the DATABASE_URL from the environment.
• If DATABASE_URL starts with postgres://, it replaces it with postgresql+psycopg2://.
• The db instance is initialized with SQLAlchemy(app) for use with SQLAlchemy ORM.
• The replacement of "postgres://" with "postgresql+psycopg2://" is necessary because of a compatibility issue between the URI format provided by Heroku and the URI format expected by SQLAlchemy.

<?php
// Load WordPress environment
require_once('/path/to/your/wp-load.php');

// Get all posts (any post type)
$args = array(
    'post_type'      => 'any', // 'any' retrieves all post types (posts, pages, custom post types)
    'post_status'    => 'any', // 'any' retrieves all post statuses
    'posts_per_page' => -1,    // Retrieve all posts
);

$all_posts = get_posts($args);

foreach ($all_posts as $post) {
    // Get the post ID
    $post_id = $post->ID;

    // Check if the post has attachments (media files)
    $attachments = get_attached_media('', $post_id);

    // Delete each attachment associated with the post
    foreach ($attachments as $attachment) {
        $attachment_id = $attachment->ID;
        // This deletes the file from the uploads directory and the database record
        wp_delete_attachment($attachment_id, true);
    }

    // Delete the post itself
    wp_delete_post($post_id, true); // true = force delete, bypass trash
}

echo 'All posts and their uploads have been deleted.';

• Backup: Make sure you have a backup of your database and uploads folder before running this script.
• Use on a staging site: Test it on a staging environment before running on a live site, as it will permanently delete all posts and their uploads.

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• Copy and Paste in tmux:
• Copy: Ctrl + B then [, navigate to the text, press Enter to copy.
• Paste: Ctrl + B then ].

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const express = require('express');
const { ApolloServer, gql } = require('apollo-server-express');

// Sample data
let books = [
    { title: 'The Great Gatsby', author: 'F. Scott Fitzgerald' },
    { title: 'To Kill a Mockingbird', author: 'Harper Lee' },
];

// GraphQL schema definition
const typeDefs = gql`
    type Book {
        title: String!
        author: String!
    }

    type Query {
        books: [Book]
    }

    type Mutation {
        addBook(title: String!, author: String!): Book
    }
`;

// GraphQL resolvers
const resolvers = {
    Query: {
        books: () => books,
    },
    Mutation: {
        addBook: (_, { title, author }) => {
            const newBook = { title, author };
            books.push(newBook);
            return newBook;
        },
    },
};

// Create Apollo server
const server = new ApolloServer({ typeDefs, resolvers });

const app = express();
server.applyMiddleware({ app });

app.listen({ port: 4000 }, () =>
    console.log(`🚀 Server ready at http://localhost:4000${server.graphqlPath}`)
);

• Schema Definition: The typeDefs defines a simple schema with a Book type and queries to fetch books and add a new book.
• Resolvers: Functions that resolve the queries and mutations. In this case, they return all books and add a new book to the list.

Here’s an example of how to use the useFetch hook in a React component to fetch and display data.

import React from 'react';
import useFetch from './useFetch'; // Ensure correct import path

function UserList() {
    const { data, loading, error } = useFetch('https://jsonplaceholder.typicode.com/users');

    if (loading) return <p>Loading...</p>;
    if (error) return <p>Error: {error.message}</p>;

    return (
        <ul>
            {data.map(user => (
                <li key={user.id}>{user.name}</li>
            ))}
        </ul>
    );
}

export default UserList;

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using System;
using System.IO;

class ReadFileExample
{
    static void Main()
    {
        string path = @"C:\example.txt";
        string text = File.ReadAllText(path);
        Console.WriteLine(text);
    }
}

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-- For SQL Server
SELECT TOP 10 * FROM Customers;

-- For MySQL and PostgreSQL
SELECT * FROM Customers LIMIT 10;

-- For Oracle
SELECT * FROM (SELECT * FROM Customers) WHERE ROWNUM <= 10;

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