Filtering, Sorting, and Calculating Data

Filtering, Sorting, and Calculating Data



Advanced Filtering:

  1. Comparison Operators for Complex Conditions:

   - Building on the basics, we explore comparison operators like !=, <>, >=, and <= for more intricate conditions.

   - Example:


     SELECT * FROM orders WHERE total_amount >= 1000 AND status != 'Shipped';



  1. Efficient Filtering Techniques:

   - BETWEEN: Select values within a given range.

   - IN: Filters data based on a predefined list of values.

   - LIKE: Enables pattern-matching for string values.

   - IS NULL: Filters out records with NULL values.


   - Examples:


     -- Using BETWEEN

     SELECT * FROM products WHERE price BETWEEN 10 AND 50;


     -- Using IN

     SELECT * FROM employees WHERE department_id IN (101, 102, 103);


     -- Using LIKE

     SELECT * FROM customers WHERE last_name LIKE 'Sm%';


     -- Using IS NULL

     SELECT * FROM orders WHERE shipping_address IS NULL;



Advanced Sorting:


  1. Sorting by Multiple Columns:

   - Enhance your ORDER BY skills by sorting data based on multiple columns.

   - Example:


     SELECT * FROM products ORDER BY category, price DESC;



  1. Custom Sorting Criteria:

   - ORDER BY is not limited to column names. You can also sort based on expressions or custom criteria.

   - Example:


     SELECT * FROM customers ORDER BY LENGTH(first_name), last_name;



  1. Benefits of Advanced Sorting:

   - Gain insights by sorting data based on specific business requirements.

   - Real-world scenario:

     - Sorting products by availability and price for an e-commerce platform.


Calculating Data:


  1. Introduction to Mathematical and String Functions:

   - Elevate your data manipulation game with functions like ABS, ROUND, and LENGTH.

   - Example:


     SELECT product_name, ABS(price_change) AS absolute_change FROM price_history;



  1. Arithmetic Operations in SELECT Statements:

   - Perform calculations directly in SELECT statements.

   - Example:


     SELECT quantity, price, quantity * price AS total_price FROM order_items;



  1. String Functions for Enhanced Manipulation:

   - Concatenate strings, extract substrings, and more with functions like CONCAT, SUBSTRING, and CHAR_LENGTH.

   - Example:


     SELECT CONCAT(first_name, ' ', last_name) AS full_name FROM employees;



Case Statements:


  1. Understanding the CASE Statement:

   - Unleash the power of conditional logic with the CASE statement.

   - Example:


     SELECT product_name, 


                WHEN stock_quantity > 50 THEN 'In Stock'

                WHEN stock_quantity <= 50 AND stock_quantity > 0 THEN 'Low Stock'

                ELSE 'Out of Stock'

            END AS stock_status

     FROM products;



  1. Versatility of CASE Statements:

    - Implement CASE in SELECT, WHERE, and ORDER BY clauses for dynamic data handling.

    - Real-world example:

      - Adjusting product pricing based on stock availability.


Practical Exercises:


  1. Hands-On Mastery:

    - Engage in hands-on exercises that integrate advanced filtering, sorting, and calculations.

    - Solve real-world problems with SQL queries, reinforcing your skills.

    - Collaborate with peers to enhance problem-solving abilities.


Key Takeaways:

- Advanced Skills Acquired: Participants will gain proficiency in advanced filtering, sorting, and calculating data.

- Complex Query Handling: Develop the ability to handle complex queries for efficient data manipulation.


Congratulations on reaching this stage of our SQL and MySQL course! Stay tuned for Module 3, where we'll unravel the mysteries of subqueries and joins. Keep practicing and happy querying!