SQL From A to Z from absolute scratch - Learn SQL with MySQL

Learn to retrieve data from a database using the select statement, selecting a database with use, and querying the customers table with from, where, order by, and semicolon termination.

Explore the select clause by using an asterisk or explicit columns, apply arithmetic expressions, alias results, control operator precedence with parentheses, and remove duplicates with distinct.

Explore the where clause and comparison operators in SQL, filtering customers by points greater than 3000 and state equals Virginia, using quotes for strings and underscores for column names.

Explore how to combine search conditions in SQL using and, or, and not, understand operator precedence with parentheses, and see examples like birth after 1990, points greater than 1000.

Learn how to use the in operator in SQL to simplify queries, replacing multiple or conditions with a concise list, and explore not in queries for exclusion.

Master the between operator in SQL to select numeric ranges like points between 1000 and 3000 and date ranges like birth dates between 1990-01-01 and 2000-01-01.

Use the like operator in SQL to match patterns with percent and underscore wildcards, with examples filtering last names starting with b or containing b, and using not to exclude.

Learn to use the regexp operator in SQL to search strings with regular expressions, including patterns using carrot and dollar sign, the pipe for or, and character classes and ranges.

Master the is not operator in SQL to find records with missing values, such as absent phone numbers or ship dates, and write queries for orders not yet shipped.

Learn to use the order by clause to sort query results by id, first name, or state, with multiple columns, asc/desc, and aliases or expressions, while avoiding column-position sorting.

Learn to use the limit clause to cap results and paginate data with an optional offset, including ordering by points and retrieving the top three customers.

Learn to select data from multiple tables with inner joins and aliases, displaying orders alongside customer full names and resolving ambiguous columns.

Learn to join tables across multiple databases by prefixing tables with their database name, and understand when to scope queries to the current database for accurate results.

Discover how to perform a self join to pair employees with their managers, using aliases and prefixed columns to output each employee and their manager's name.

Learn to write multi-table SQL queries by joining three or more tables, using aliases and precise join conditions to produce detailed reports with customer names, order statuses, and payments.

Learn how composite primary keys identify records across multi-column tables and implement compound join conditions by joining order items with item notes on both order id and product id.

Learn implicit join syntax and its equivalence to explicit inner joins with table aliases, and why omitting the join clause risks cross joins, so use explicit syntax instead.

Explore outer joins, show how left and right joins return all records from the left or right table, contrast with inner joins, and practice using outer joins.

Discover how outer joins combine multiple tables to return all records, including unmatched rows, by using left joins with customers, orders, shippers, and order statuses.

Explore self joins on an employees table to connect each employee with their manager, using left join to include employees who have no manager.

Learn how the using clause simplifies joins by matching column names across tables, replacing on conditions for cleaner queries, with examples from orders, customers, shippers, and payments, including composite keys.

Explore natural joins as a simple way to join tables by common column names, but learn why this approach can yield unexpected results and is discouraged.

Explore cross joins by combining every record from two tables, illustrated with customers and products, and compare explicit versus implicit syntax for practical use.

Master unions in SQL by combining rows from queries with identical column counts. Rename columns and create unified results, including bronze, silver, gold customer types and active vs archived labels.

Explore column attributes in MySQL: understand integer primary keys, varchar(50) vs char(50) storage, not null and null values, auto increment, and default values for efficient tables.

Learn to insert a row into a table using insert into, handle auto incremented customer_id with default or null, and supply optional fields like birth date and city.

Insert multiple rows in a single statement using insert into shippers (name) values (...), (...), (...); rely on auto generated shipper ids and verify results in the shippers table.

Learn to insert data into multiple tables using a parent-child relationship between orders and order items, and retrieve the new order id with last insert id to populate items.

Copy data between tables efficiently with create table as select and subqueries, truncate, filter records before 2019, and join to replace client id with client name for archive tables.

Update a single row in the invoices table with the update statement and set clause to modify payment total and payment date by invoice_id. Learn about defaults and 50% calculations.

Learn to update multiple rows with a single update statement using a general where clause, and disable safe updates in MySQL Workbench while applying expressions.

Learn to use subqueries in update statements to derive client IDs, update invoices, and handle multiple IDs with IN; verify results with pre-update queries.

Learn to delete data with the delete from statement, optionally using a where clause or a subquery to target invoices by client id, avoiding deleting all records.