Auto_increment value needs to be set as S1 Hi I need to set auto increment for a table as S1. I tried by altering the table and also by creating by new table
I am aware how to set auto_increment but when i try to set auto increment as S1 i am unable to do. since i need the primary key values should be S1,S2,S3 as following records. can any one please suggest the data type for that, 

 desc test_1;
+-------+--------------+------+-----+---------+-------+
| Field | Type         | Null | Key | Default | Extra |
+-------+--------------+------+-----+---------+-------+
| id    | varchar(10)  | NO   | PRI | NULL    |       |
| name  | varchar(100) | NO   |     | NULL    |       |
+-------+--------------+------+-----+---------+-------+
2 rows in set (0.00 sec)

mysql&gt; ALTER TABLE test_1 AUTO_INCREMENT='S1';
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''S1'' at line 1

mysql&gt; create table tbl(ID varchar(100) not null primary key auto_increment,name varchar(100)) auto_increment='s1';
ERROR 1063 (42000): Incorrect column specifier for column 'ID'
mysql&gt; create table tbl(ID text not null primary key auto_increment,name varchar(100)) auto_increment='s1';
ERROR 1063 (42000): Incorrect column specifier for column 'ID'
mysql&gt; create table tbl(ID varchar(100) not null primary key auto_increment,name varchar(100)) auto_increment='s';
ERROR 1063 (42000): Incorrect column specifier for column 'ID'
Autoincrement values can only be numeric (integer and floats types if I remember correctly).

If you want to store S1, ...., S1000, just store an integer, and return the extra S on select or on client side:

create table tbl(ID bigint not null primary key auto_increment,name varchar(100)) auto_increment=1;

insert into tbl (name) values ('a');
...

select concat('S', id) as id, name from tbl;
+----+------+
| id | name |
+----+------+
| S1 | a    |
| S2 | a    |
| S3 | a    |
| S4 | a    |
...