Add an autoincrement column with a custom start value in MySQL
To add a new column to an already created table, use ALTER TABLE and ADD COLUMN. Use AUTO_INCREMENT to set auto increment custom value.
Let us first create a table −
mysql> create table DemoTable
-> (
-> StudentName varchar(20)
-> );
Query OK, 0 rows affected (0.63 sec)
Insert some records in the table using insert command −
mysql> insert into DemoTable values('Robert');
Query OK, 1 row affected (0.12 sec)
mysql> insert into DemoTable values('Adam');
Query OK, 1 row affected (0.13 sec)
mysql> insert into DemoTable values('Mike');
Query OK, 1 row affected (0.12 sec)Display all records from the table using select statement −
mysql> select *from DemoTable;
This will produce the following output −
+-------------+
| StudentName |
+-------------+
| Robert |
| Adam |
| Mike |
+-------------+
3 rows in set (0.00 sec)
Following is the query to add an autoincrement column with start value −
mysql> alter table DemoTable add column StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY,AUTO_INCREMENT=1000;
Query OK, 0 rows affected (1.83 sec)
Records: 0 Duplicates: 0 Warnings: 0
Let us check the table records once again −
mysql> select *from DemoTable;
This will produce the following output −
+-------------+-----------+
| StudentName | StudentId |
+-------------+-----------+
| Robert | 1000 |
| Adam | 1001 |
| Mike | 1002 |
+-------------+-----------+
3 rows in set (0.00 sec)
Published on 13-Dec-2019 10:54:18
