WHERE vs WhereEwpression in Query ou Select expression

Hi all,

Can someone tell me wath is the main difference beetween WHERE and WhereEwpression when writing Query ?

SubSonic.SqlQuery sql = new Select().From(PREV331R.Schema).Where(PREV331R.Columns.Idprev101e).IsEqualTo(clespace.Value);

or

SubSonic.SqlQuery sql = new Select().From(PREV331R.Schema).WhereBLOCKED EXPRESSION;

Whath is the correct one ?

Thank's

G.

 a WhereExpression allows you to enter a string - like "Thing=1" and we parse it into a proper argument with parameters.