Module Overview

What You’ll Learn

• Insert data into tables
• Update existing records
• Delete records
• Retrieve inserted data

💡 Why this module matters: A table with no data in it isn’t useful yet. CRUD, Create, Read, Update, Delete, is the full lifecycle of a row, and this module covers the three-quarters of it that aren’t SELECT: getting data in, changing it, and taking it back out.

What’s Covered

• INSERT, adding a single row to a table.
• INSERT multiple rows, adding several rows in one statement.
• INSERT … SELECT, copying rows from one query straight into a table.
• UPDATE, changing existing rows.
• DELETE, removing rows.
• RETURNING clause, getting back exactly the rows a statement just changed.

Hands-On

By the end of this module, you’ll insert sample records, update selected rows, delete records, and use RETURNING to see exactly what changed, all while building a small employee database of your own.

Next module turns to the tables themselves again, changing their structure after the fact with ALTER TABLE.