【My Study Note】Add, Change, and Drop Columns
MySQL Programming
Add, Change, and Drop Columns
1. Preparing the data
// Create a database
CREATE DATABASE shop_app;
// Check if the database is created or not
SHOW DATABASES;
// Select the database
USE shop_app;
// Creating a table for Mac
CREATE TABLE items(id INT AUTO_INCREMENT, name TEXT, price INT, category TEXT, PRIMARY KEY(id));
// Creating a table for Windows
CREATE TABLE items(id INT AUTO_INCREMENT, name TEXT, price INT, category TEXT, PRIMARY KEY(id)) DEFAULT CHARSET=utf8;
// Check if it's successfully created
SHOW TABLES;
// Insert the data
INSERT INTO items(name, price, category) VALUES ('Carrot', 60, 'Vegetables');
2. Add a Column
ALTER TABLE tableName ADD COLUMN newColumn INT;
3. Change a Column
ALTER TABLE tableName CHANGE COLUMN originalColumn newColumn INT;
4. Drop a Column
ALTER TABLE tableName DROP COLUMN columnName;
MySQL Programming
