SQL: Updating a table structure

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We can alter an existing table structure visually with TablePlus, but we can do that using SQL too, using the ALTER TABLE command, followed by the alteration you want to make:

ALTER TABLE people ADD COLUMN born_year INTEGER;

This will add a new column with empty values:

We can drop a column in this way:

ALTER TABLE people DROP COLUMN born_year;

Lessons in this unit:

0: Introduction
1: Using TablePlus
2: Create a Postgres database
3: Create a new table
4: Add data to a table
5: Query data with SELECT
6: Delete data from the database
7: Update data with UPDATE
8: Null constraints
9: Unique and primary keys
10: ▶︎ Updating a table structure
11: Joins
12: SQL Views
13: SQL, copy data from one table to another