SQL Course for Beginner

Understand how tables organize data into rows and columns, converting binary storage into readable tabular formats with an employee example and a consistent table definition across databases.

Learn to create an Oracle table using the syntax create table table_name (column data_type). Implement a two-column example with id integer and name varchar2(20) in a 19c pluggable database.

Explore system tables and views in Oracle databases and distinguish them from user created tables. Learn how metadata stores database information, user accounts, and data files after installation.

Master the alter table statement in sql to add, rename, modify, or drop columns, change data types, and rename tables with practical examples.

Discover how to create a new table with create table as select (ctas), copying all or selected columns from an existing table and applying optional conditions to filter data.

Learn to insert data into a two-column table using two syntaxes: insert into table values (...) and insert into table (column1, column2) values (...); commit to finalize.

Learn to retrieve table data with SQL by using describe to view columns and select statements, including select * and selecting specific columns like name.

Learn how the update statement changes a record in a database, using a practical example to update an employee salary from 10000 to 20000 with a where condition.

Explore how to perform an update in SQL by changing a column value, such as an employee email, with a where clause and commit on a 1000-record table.

Learn how to fetch a subset of records in Oracle SQL using the fetch clause, limit results, and select specific columns like name and email for efficient queries.

Learn how to drop a table in Oracle, including syntax, constraints and referential integrity, and how the recycle bin and purge option affect space release.

Learn how data types define what data a table column stores, with integers for ids, and how to specify data types when creating tables in Oracle and other databases.

Learn how the order by clause sorts query results in SQL, with default ascending order and the option to specify descending order on any column.

Learn how to use the select distinct statement to identify unique values, such as distinct countries from an employee table, and avoid using star for column-specific queries.

Learn to filter records using the and operator to combine multiple conditions, such as gender and country, for example all female records from China.

Understand how the or operator in SQL combines multiple conditions, returning true if any condition is met, with gender and country examples in select, update, and delete.

Use the between clause in SQL to filter records within a range, such as salaries between 500 and 800 or years between 1988 and 2002, including select, delete, and update.

Learn how to filter data in sql using the in operator by listing multiple years in a where clause, turning lengthy conditions into a simple year list.

Learn to use the SQL average aggregate function on the salary column of the employee table to compute the average salary, with an optional alias such as average salary.

Learn how to use the sum aggregate function to total salaries in a table, optionally filter by country or gender, and compare results with the average.

Explore transaction control in Oracle database, mastering insert, update, and delete operations, and learning how commit makes changes permanent while rollback undoes uncommitted actions.

Learn how rollback restores data after delete operations in sql, and why commit makes changes permanent, with practical examples of deleting records and checking counts.

Generate mock data for sql practice with a free generator, creating a table for city, gender, and email, then load 1000 dummy records and practice select queries with where.

Discover the role of SQL, the standard language for querying databases, and learn how to download and install Oracle 21c Express Edition on Windows for practice.