I know in Oracle you can use DBA_TAB_COLUMNS (or ALL_TAB_COLUMNS). My SQL Server knowledge is very rusty, but can't you use the INFORMATION_SCHEMA.COLUMNS view?
I've said it before and I'll say it again: If you want to speed up your application, don't look at your code, look at your data access. The two slowest things you can do in application development are ...
Arthur Fuller explores the value of identity columns and the usefulness of their arbitrary values and discusses ways to use SQL Server 2000's IDENTITY_INSERT setting. Despite your numerous ...