It depends on the table schema. You can not leave fields blank that have no default or autogenerated value, but have a not null constraint.
CREATE TABLE #tmp(
id INT NOT NULL identity(1,1),
now DATETIME NOT NULL CONSTRAINT DF_MyTable_CreateDate_GETDATE DEFAULT GETDATE(),
name varchar(100) not null,
address varchar(100)
)
insert into #tmp(now, name, address) values('2013.01.01 10:25:00', 'John', 'Paris');
insert into #tmp(name, address) values('Peter', 'Berlin');
insert into #tmp(name) values('Bianca');
insert into #tmp(address) values('Bratislava');
select * from #tmp;
DROP TABLE #tmp
From here on, everything is normal ADO.NET:
Simple ADO.NET Database Read, Insert, Update and Delete using C#.[
^]