Database and SQL foundations
Tables, relationships and SELECT / INSERT / UPDATE / DELETE on classroom data only.
Objectives
- Describe a table as rows and columns
- Write the purpose of SELECT and WHERE
- State that the lab uses fake practice tables
Skills: SQL · Tables · Queries
Tables and relationships
A table has a name, columns and rows. A key uniquely identifies a row. Relationships connect tables (for example student id on a marks table). Database design starts with clear names and one fact per column. GROUP BY and subqueries come after you can filter with WHERE.
SELECT, INSERT, UPDATE, DELETE
SELECT reads. INSERT adds. UPDATE changes. DELETE removes. JOIN combines tables. The Sharda classroom SQL engine uses fake tables such as students and products — never the production vendors or users tables. Passing a lab SELECT does not mean you may run SQL on the live site.