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-rw-r--r--lib/sqlalchemy/mods/selectresults.py84
1 files changed, 84 insertions, 0 deletions
diff --git a/lib/sqlalchemy/mods/selectresults.py b/lib/sqlalchemy/mods/selectresults.py
new file mode 100644
index 000000000..9613d8fc0
--- /dev/null
+++ b/lib/sqlalchemy/mods/selectresults.py
@@ -0,0 +1,84 @@
+import sqlalchemy.sql as sql
+
+import sqlalchemy.mapping as mapping
+
+def install_plugin():
+ mapping.extensions.append(SelectResultsExt)
+
+class SelectResultsExt(mapping.MapperExtension):
+ def select_by(self, mapper, *args, **params):
+ return SelectResults(mapper, mapper._by_clause(*args, **params))
+ def select(self, mapper, arg=None, **kwargs):
+ if arg is not None and isinstance(arg, sql.Selectable):
+ return mapping.EXT_PASS
+ else:
+ return SelectResults(mapper, arg, ops=kwargs)
+
+class SelectResults(object):
+ def __init__(self, mapper, clause=None, ops={}):
+ self._mapper = mapper
+ self._clause = clause
+ self._ops = {}
+ self._ops.update(ops)
+
+ def count(self):
+ return self._mapper.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._mapper, 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=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=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._mapper.select_whereclause(self._clause, **self._ops))