MySQL Note: Auto Increment Attribute in MySQL

• Auto increment attribute can be applied to a column that is set as a key.
• Whenever we insert a new row, our primary key can be populated automatically.
• Then each subsequent row is auto incremented.
  So, below sections show how we can do it.

• Create a table, let's say, here we want to create a transaction table.

CREATE TABLE transactions (
	transaction_id INT PRIMARY KEY AUTO_INCREMENT,
	amount DECIMAL (5, 2)
)

• Note that, if we want the number to start with other number than 1, we need to set it. In this example, by default, the transaction_id will start at 1.
• Then, Insert a value into the table.

INSERT INTO transactons (amount)
VALUES (4.99);
SELECT * FROM transactions;

• Try insert another value into the table to see how it work.

INSERT INTO transactons (amount)
VALUES (3.58);
SELECT * FROM transactions;

• So, you can continue adding the data from here.

• Create a table, let's say, here we want to create a transaction table. Here, you need to specifically state the specific value, for instance, 1000.

CREATE TABLE transactions (
	transaction_id INT PRIMARY KEY AUTO_INCREMENT = 1000,
	amount DECIMAL (5, 2)
)

• Insert a value into the table.

INSERT INTO transactons (amount)
VALUES (4.99);
SELECT * FROM transactions;

• Try insert another value into the table to see how it work.

INSERT INTO transactons (amount)
VALUES (3.58);
SELECT * FROM transactions;

• So, you can continue adding the data from here.