Question

所以我正在尝试使用python为sql炼金术调用构建多个过滤器。我

query = MyModel.query

if 'column1' in data:
    try:
        value = int(data['column1'])
    except (TypeError, ValueError):
        pass
    else:
        query = query.filter(MyModel.column1 == value)

if 'column2' in data:
    try:
        value = datetime.utcfromtimestamp(int(data['column2']))
    except (TypeError, ValueError):
        pass
    else:
        query = query.filter(or_(MyModel.column2 >= value))

# etc.

return query

我只是这样做，因为数据对象中的属性会有所不同，我不知道数据对象中的过滤器会得到什么。现在，当我执行查询时...语句 ANDs 两个过滤器，无论我在第二个过滤器查询中放入的还是_ 。为了使查询正常工作，我需要更改什么？

Answer 1

首先收集约束，然后应用or_：

constraints = []
if 'column1' in data:
    try:
        value = int(data['column1'])
    except (TypeError, ValueError):
        pass
    else:
        constraints.append(MyModel.column1 == value)

if 'column2' in data:
    try:
        value = datetime.utcfromtimestamp(int(data['column2']))
    except (TypeError, ValueError):
        pass
    else:
        constraints.append(MyModel.column2 >= value)

if constraints:
    query = query.filter(or_(*constraints))

或多个SQL Alchemy查询过滤器

1 个答案: