What are some common mistakes beginners make in data scraping, and how can they be avoided?

Common mistakes in web scraping include ignoring a website’s robots.txt file, which can lead to legal issues, and sending requests too quickly, risking IP bans by overloading servers. Beginners often overlook handling errors, such as timeouts or broken URLs, which can cause the script to stop unexpectedly. Additionally, many fail to use tools like BeautifulSoup or XPath correctly for parsing, leading to incorrect data extraction. To avoid these, always check and respect robots.txt, add delays (using time.sleep()), handle exceptions with try-except blocks, and use appropriate parsers with clear CSS selectors or XPath expressions.

Failing to choose the right tool for automating the data scraping process is a common mistake beginners make. Depending on how the website is designed, always avoid browser-based solutions such as selenium for web scraping-related tasks wherever possible. To ensure an efficient software solution, always think about speed, resource usage, and accuracy.

Initially try looking for available API services that a website offers so that the scraping process can be done faster and officially through the API services. If a website doesn't have an API, then you may try normal ways of accessing the web page and using Beautiful Soup(in Python language) for parsing data, and in worst cases, using a browser-based formula is fine.

When using regular expressions for pattern matching on the data, make sure that the target computer hardware is good enough to run those patterns as regular expression-based matching consumes more CPU usage compared to Beautiful Soup-based data extraction methods.

If you need to conduct data extraction on a very large number of records, multithreading is a solution that you can try to speed up the execution. But keep in mind, that the target server should have the capability and bandwidth availability to handle such an amount of concurrent requests. You may integrate proxies in those situations. 

When you're not using proxies, follow robots.txt rules if it has any, ensure enough delays, and avoid running into honey traps efficiently to avoid getting blocked by the target website. 

If you're web scraping whole website pages, trying to find the sitemap of the website and getting the direct link to it is a good approach to save time. 

Ignoring robots.txt and website terms of service is the most important part, in my opinion.

Always read and follow robots.txt and site regulations before scraping.
Also scraping too aggressively. Implement rate limitation and waits between queries to ensure everything is under control.