fixes #6

fastlite/kw.py

@@ -15,11 +15,37 @@ def xtra(self:Table, **kwargs):
 @patch
 def get_last(self:Table, as_cls:bool=True):
     row = first(self.rows_where('_rowid_=?', (self.last_rowid,)))
+    assert row, f"Couldn't find {self.last_rowid}"
     vals = [row[pk] for pk in self.pks]
     self.last_pk = vals[0] if len(vals)==1 else vals
     if as_cls and hasattr(self,'cls'): row = self.cls(**row)
     return row
 
+@patch
+def ids_and_rows_where(
+    self:Table,
+    where: Optional[str] = None,
+    where_args: Optional[Union[Iterable, dict]] = None,
+    order_by: Optional[str] = None,
+    limit: Optional[int] = None,
+    offset: Optional[int] = None,
+) -> Generator[Tuple[Any, Dict], None, None]:
+    """
+    Like ``.rows_where()`` but returns ``(rowid, row)`` pairs.
+
+    :param where: SQL where fragment to use, for example ``id > ?``
+    :param where_args: Parameters to use with that fragment - an iterable for ``id > ?``
+      parameters, or a dictionary for ``id > :id``
+    :param order_by: Column or fragment of SQL to order by
+    :param select: Comma-separated list of columns to select - defaults to ``*``
+    :param limit: Integer number of rows to limit to
+    :param offset: Integer for SQL offset
+    """
+    cs = [c.name for c in self.columns]
+    select = ",".join("[{}]".format(c) for c in cs)
+    select = "_rowid_ as __rid, " + select
+    for row in self.rows_where(select=select, where=where, where_args=where_args, order_by=order_by, limit=limit, offset=offset):
+        yield row.pop('__rid'), row
 
 @patch
 def get(self:Table, pk_values: list|tuple|str|int, as_cls:bool=True)->Any:
@@ -28,14 +54,13 @@ def get(self:Table, pk_values: list|tuple|str|int, as_cls:bool=True)->Any:
     xtra = getattr(self, 'xtra_id', {})
     vals = pk_values + list(xtra.values())
     pks = self.pks + list(xtra.keys())
-    if len(pks) != len(vals):
-        raise NotFoundError( "Need {} primary key value{}".format( len(pks), "" if len(pks) == 1 else "s"))
-
+    if len(pks)!=len(vals): raise NotFoundError(f"Need {len(pks)} pk")
     wheres = ["[{}] = ?".format(pk_name) for pk_name in pks]
-    rows = self.rows_where(" and ".join(wheres), vals)
-    try: row = list(rows)[0]
-    except IndexError: raise NotFoundError
+    item = first(self.ids_and_rows_where(" and ".join(wheres), vals))
+    if not item: raise NotFoundError
+    rid,row = item
     self.last_pk = last_pk
+    self.last_rowid = rid
     if as_cls and hasattr(self,'cls'): row = self.cls(**row)
     return row