merged 0.2 branch into trunk; 0.1 now in sqlalchemy/branches/rel_0_1

1 files changed, 82 insertions, 0 deletions

diff --git a/lib/sqlalchemy/ext/selectresults.py b/lib/sqlalchemy/ext/selectresults.py
new file mode 100644
index 000000000..5ba9153dd
--- /dev/null
+++ b/lib/sqlalchemy/ext/selectresults.py
@@ -0,0 +1,82 @@
+import sqlalchemy.sql as sql
+
+import sqlalchemy.orm as orm
+
+
+class SelectResultsExt(orm.MapperExtension):
+    def select_by(self, query, *args, **params):
+        return SelectResults(query, query.join_by(*args, **params))
+    def select(self, query, arg=None, **kwargs):
+        if arg is not None and isinstance(arg, sql.Selectable):
+            return orm.EXT_PASS
+        else:
+            return SelectResults(query, arg, ops=kwargs)
+
+class SelectResults(object):
+    def __init__(self, query, clause=None, ops={}):
+        self._query = query
+        self._clause = clause
+        self._ops = {}
+        self._ops.update(ops)
+
+    def count(self):
+        return self._query.count(self._clause)
+    
+    def min(self, col):
+        return sql.select([sql.func.min(col)], self._clause, **self._ops).scalar()
+
+    def max(self, col):
+        return sql.select([sql.func.max(col)], self._clause, **self._ops).scalar()
+
+    def sum(self, col):
+        return sql.select([sql.func.sum(col)], self._clause, **self._ops).scalar()
+
+    def avg(self, col):
+        return sql.select([sql.func.avg(col)], self._clause, **self._ops).scalar()
+
+    def clone(self):
+        return SelectResults(self._query, self._clause, self._ops.copy())
+        
+    def filter(self, clause):
+        new = self.clone()
+        new._clause = sql.and_(self._clause, clause)
+        return new
+
+    def order_by(self, order_by):
+        new = self.clone()
+        new._ops['order_by'] = order_by
+        return new
+
+    def limit(self, limit):
+        return self[:limit]
+
+    def offset(self, offset):
+        return self[offset:]
+
+    def list(self):
+        return list(self)
+        
+    def __getitem__(self, item):
+        if isinstance(item, slice):
+            start = item.start
+            stop = item.stop
+            if (isinstance(start, int) and start < 0) or \
+               (isinstance(stop, int) and stop < 0):
+                return list(self)[item]
+            else:
+                res = self.clone()
+                if start is not None and stop is not None:
+                    res._ops.update(dict(offset=self._ops.get('offset', 0)+start, limit=stop-start))
+                elif start is None and stop is not None:
+                    res._ops.update(dict(limit=stop))
+                elif start is not None and stop is None:
+                    res._ops.update(dict(offset=self._ops.get('offset', 0)+start))
+                if item.step is not None:
+                    return list(res)[None:None:item.step]
+                else:
+                    return res
+        else:
+            return list(self[item:item+1])[0]
+    
+    def __iter__(self):
+        return iter(self._query.select_whereclause(self._clause, **self._ops))