How to set initial value and auto increment in MySQL ?

How to set initial value and auto increment in MySQL ?

we can use below command -

ALTER TABLE employee AUTO_INCREMENT=1001;

or if you haven't already added an id column, also add it

ALTER TABLE employee ADD id INT UNSIGNED NOT NULL AUTO_INCREMENT,
    ADD INDEX (id);

Example :-

MySQL - Setup an auto-incrementing primary key that starts at 20001:

Step 1.  create your table:

create table employee(

  id       int(11) auto_increment, 

  name varchar(40),

  PRIMARY KEY (id)

)

Step 2 set the start number for auto increment primary key:

ALTER TABLE employee AUTO_INCREMENT=20001;

Step 3 insert some rows:-

insert into employee (name) values("pappu");

insert into employee(name) values("mamu");

Step 4, interpret the output:

select * from employee

'20001', 'pappu'

'20002', 'mamu'

If you need to add column for auto increment

alter table employee add column id int(5) NOT NULL AUTO_INCREMENT FIRST

This query for add column at first. Now you have to reset auto increment initial value. So use this query 

alter table employee AUTO_INCREMENT=20001