Relational Databases and SQL

Module 1: Foundations and key ideas

• Client server architectures and how apps talk to databases
• Databases and database types relational, key value, document at a glance
• Important terms table, row, column, key, constraint, index
• Structure of relational databases tables, keys, and relations

Module 2: Core building blocks

• Primary keys purpose, uniqueness, and good choices
• Relationships and foreign keys the glue between tables
• SQL overview statements, clauses, and query lifecycle

Module 3: Database schemas

• What a schema is and why it matters
• Planning a schema from requirements to tables and keys
• Attributes naming, types, nullability, and defaults
• Primary keys and when to use a composite primary key

Module 4: Relationships in practice

• Terms for entities, attributes, and associations
• One to one patterns and when to apply them
• One to many the most common structure
• Many to many with junction tables
• Referential integrity and cascades

Module 5: Querying with SQL

• SELECT, FROM, WHERE basics with operators and functions
• ORDER BY, LIMIT or FETCH, DISTINCT for tidy results
• JOIN types inner, left, right and how to pick the right one
• GROUP BY and HAVING for summaries

Module 6: Changing data and safeguarding it

• INSERT, UPDATE, DELETE with safe patterns
• Constraints NOT NULL, UNIQUE, CHECK and when to use them
• Transactions and ACID basics commit and rollback
• Simple isolation level overview and common pitfalls

Module 7: Structure, quality, and performance basics

• Normal forms 1NF, 2NF, 3NF in plain language
• Indexes how they help and when they hurt
• Views for reusable queries and security
• Simple ER diagrams and naming standards

Module 8: Practical examples

• To do list schema tasks, lists, users, and relationships
• Another example small shop or library with core tables
• Example queries reports, recent items, and summaries
• Handover checklist backups, access, and change control