小白求助， flask_sqlalchemy 条件查询的一个问题

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This topic created in 2306 days ago, the information mentioned may be changed or developed.

如果条件为 None，怎样能返回所有的数据呢，现在是直接在 sql 里变成“where 字段 IS NULL”了

5 replies • 2022-03-25 08:39:28 +08:00

knightdf

Jan 7, 2020

```python
filters = []
if xxx is not None:
filters.append(Model.attr == xxx)
.query.filter(*filters).xxxx
```

hp66722667

Jan 7, 2020

通过 if 判断一下字段，不就可以随便拼接 sql 语句了么

6167

Jan 7, 2020

```
if not xxx:
data = Xxx.query.all()
```

SjwNo1

Jan 7, 2020

你都用 SQLAlchemy 了~~
'''
if cond is None:
objs = Xxx.query.all()
'''

luckyc

Mar 25, 2022

```
filters = [OrderModel.date == date] if isinstance(date, str) else [OrderModel.date.in_(date)]
filters += [OrderModel.type.in_(type)] if type else []
filters += [OrderModel.successed == successed] if successed else []
order_list = OrderModel.query.filter(*filters).all()
order_name = [f.name for f in order_list]
return list(set(order_name))

```