Below is a snippet of SQL code that I use to add transaction-time columns to a database table.

a) when and who created a record

b) when and who updated a record

Snodgrass refers to a table with these columns as a transaction-time state table.

alter table [table1] add [CreateDate] [smalldatetime] NOT NULL CONSTRAINT [DF_table1_CreateDate] DEFAULT (getdate())
alter table [table1] add [CreateUserId] [varchar] (20) NOT NULL CONSTRAINT [DF_table1_CreateUserId] DEFAULT (suser_sname())
alter table [table1] add [UpdateDate] [smalldatetime] NOT NULL CONSTRAINT [DF_table1_UpdateDate] DEFAULT (getdate())
alter table [table1] add [UpdateUserId] [varchar] (20) NOT NULL CONSTRAINT [DF_table1_UpdateUserId] DEFAULT (suser_sname())