[sql-server] Set start value for column with autoincrement

I have a table Orders with the following fields:

Id | SubTotal | Tax | Shipping | DateCreated

The Id column is set to autoincrement(1,1).

This is to be used in an E-commerce storefront. Sometimes a current E-commerce store is migrated to my platform and they already have orders - which could mean that their current Order.Id is, for example, 9586.

I want to have the autoincrement field start from that value.

How can I do this?

You need to set the Identity seed to that value:

CREATE TABLE orders
(
 id int IDENTITY(9586,1)
)

To alter an existing table:

ALTER TABLE orders ALTER COLUMN Id INT IDENTITY (9586, 1);

More info on CREATE TABLE (Transact-SQL) IDENTITY (Property)

Also note that you cannot normally set a value for an IDENTITY column. You can, however, specify the identity of rows if you set IDENTITY_INSERT to ON for your table. For example:

SET IDENTITY_INSERT Orders ON

-- do inserts here

SET IDENTITY_INSERT Orders OFF

This insert will reset the identity to the last inserted value. From MSDN:

If the value inserted is larger than the current identity value for the table, SQL Server automatically uses the new inserted value as the current identity value.

In the Table Designer on SQL Server Management Studio you can set the where the auto increment will start. Right-click on the table in Object Explorer and choose Design, then go to the Column Properties for the relevant column:

Here the autoincrement will start at 760