I want to create a new column that has a default value of the primary key in a varchar(10) format. Hows this done?
it's not done -- you cannot assign a default value of another column
why not just convert the value when you run a SELECT?
or, if you're gonna do it relentlessly on every SELECT, why not set up a view which has the extra column incorporated?
Our large dataset needs compared regularly against two seperate databases, One stores the pk as a double, the other as a string (wonderful right?) Our local copy of the dataset is only a small portion of the whole system so storing both types of primary keys for joining to both seemed useful.