USE AdventureWorks;
GO
CREATE TABLE T1 (id int , name char (20));
GO
EXEC sp_addextendedproperty
@name = N'Caption'
,@value = N'Employee ID'
,@level0type = N'Schema', @level0name = dbo
,@level1type = N'Table', @level1name = T1
,@level2type = N'Column', @level2name = id;
GO
--Update the extended property.
EXEC sp_updateextendedproperty
@name = N'Caption'
,@value = 'Employee ID must be unique.'
,@level0type = N'Schema', @level0name = dbo
,@level1type = N'Table', @level1name = T1
,@level2type = N'Column', @level2name = id;
GO