Something in SQL Server that isn’t always obvious to beginners is that when you create a default value for a column on a table, SQL Server creates a constraint (much like a primary or foreign key). All constraints must have a name, and if one isn’t specified SQL Server will generate one for you. For example:
1 2 3 4 5 CREATE TABLE [dbo].[point_types] ( [typeid] [int] NOT NULL DEFAULT(NEXT VALUE FOR [pointtypeid]) ,[typename] [nvarchar](30) NOT NULL DEFAULT 'Unspecified' ,CONSTRAINT [PK_PointType] PRIMARY KEY CLUSTERED ([typeid] ASC) ) We’ve got a simple table here and both fields have a default value set (the primary key’s value is generated from a sequence object, pointtypeid).