TypeAlias = str
SaSelect: TypeAlias = 'sa.Select[Any]'
+SaScalarSelect: TypeAlias = 'sa.ScalarSelect[Any]'
SaRow: TypeAlias = 'sa.Row[Any]'
-SaColumn: TypeAlias = 'sa.Column[Any]'
+SaColumn: TypeAlias = 'sa.ColumnElement[Any]'
+SaExpression: TypeAlias = 'sa.ColumnElement[bool]'
SaLabel: TypeAlias = 'sa.Label[Any]'
-SaTable: TypeAlias = 'sa.Table[Any]'
-SaClause: TypeAlias = 'sa.ClauseElement[Any]'
+SaFromClause: TypeAlias = 'sa.FromClause'
+SaSelectable: TypeAlias = 'sa.Selectable'