4. Извлечение данных: подробный разбор — Изучаем MySQL и MariaDB с нуля и создаем приложение для ...

Learn how to retrieve, sort, filter, and search #data in #MySQL and #base and its city table, you'll learn how to build increasingly powerful SQL queries for real-world database applications. 📚 WHAT YOU'LL LEARN In this lesson, you'll learn how to: • Retrieve data using SELECT • Retrieve all columns using SELECT * • Select specific columns from a table • Use the FROM clause • Rename result columns using AS • Sort results using ORDER BY • Sort data in ascending order with ASC • Sort data in descending order with DESC • Limit results using LIMIT • Filter records using WHERE • Compare values using SQL comparison operators • Search for patterns using LIKE • Use the % wildcard • Use the _ wildcard • Search for values using IN • Exclude values using NOT IN • Combine conditions using AND • Combine alternative conditions using OR • Use REGEXP for advanced pattern matching • Understand regular-expression metacharacters • Match characters at specific positions • Match the beginning and end of strings • Work with character ranges and character classes • Match spaces and punctuation using predefined classes 💻 SQL COMMANDS & OPERATORS COVERED SELECT FROM AS ORDER BY ASC DESC LIMIT WHERE LIKE IN NOT IN AND OR REGEXP 🔎 PATTERN MATCHING WITH LIKE & REGEXP You'll learn how MySQL and MariaDB can search for patterns inside text. With LIKE, you'll work with the % and _ wildcards to find values that begin with, end with, contain, or match specific character positions. You'll then move to REGEXP and learn more advanced pattern matching using regular-expression symbols such as ^, ., *, $, + and ?. 🌍 PRACTICAL DATABASE EXAMPLE The lesson uses the World database and its city table to demonstrate practical SQL queries involving city names, zones, and population. 🎓 WHO THIS TUTORIAL IS FOR This tutorial is suitable for: • Students learning SQL • Beginners learning MySQL • MariaDB beginners • Programming students • Aspiring software developers • Database students • Anyone learning SQL and databases from scratch 🚀 CONTINUE THE COURSE In the previous lessons, we learned how to create databases and tables and how to insert, update, and delete data. Now we move deeper into one of the most important skills in SQL: retrieving the right data from a database. Practice the queries yourself and experiment with different conditions and search patterns as you follow along. 👍 Like this video if you found it helpful. 💬 Leave a comment and tell me which SQL clause or operator you found most useful. 🔔 Subscribe and follow the complete MySQL & MariaDB course for more practical SQL, database, programming, and software development tutorials. #MySQL #SQL #MariaDB #MySQLTutorial #DatabaseTutorial 00:00 Introduction to Data Retrieval 00:24 Download & Load the World Database 01:09 CREATE DATABASE IF NOT EXISTS & USE 01:32 Understanding the City Table 01:47 Execute the SQL File 02:25 SELECT: Retrieve Data from a Table 03:09 Selecting Specific Columns 03:30 Column Aliases with AS 04:10 Sorting Data with ORDER BY 04:51 ASC vs DESC 05:07 Limiting Results with LIMIT 05:30 Filtering Data with WHERE 06:11 Filtering by Population 06:40 Pattern Matching with LIKE 07:33 Matching a Single Character with _ 07:56 Filtering with IN 08:29 Excluding Values with NOT IN 08:57 Combining Conditions with AND 09:47 Combining Conditions with OR 10:29 Introduction to REGEXP 11:21 REGEXP Metacharacters & Character Ranges 12:17 Character Sets with REGEXP 12:44 REGEXP Beginning Anchor ^ 13:21 REGEXP End Anchor $ 13:29 Matching Characters with REGEXP 13:52 One or More Matches with + 14:15 Optional Matches with ? 14:32 REGEXP Predefined Character Classes 14:52 Matching Punctuation with [:punct:] 15:05 More REGEXP Character Classes