Question

我想从ajax查询我的数据库中的记录，例如浮点变量（地图坐标）。（查询浮点列）。我不确定类似的方法是否可以查询字符串以外的数据类型，因为这不起作用......

data = json.loads(request.data)

        markers = session.query(Markers) \
        .filter( Markers.lat.like( '%' + data['lat'] + '%' ) ) \
        .filter( Markers.lng.like( '%' + data['lng'] + '%' ) ) \
        .order_by(func.random()).limit(7).all()

        if len(markers) <= 0:
            return jsonify( resp = 'no results' )
        else:
            return jsonify( resp = 'markers', markers = [m.serialize for m in markers] )

我甚至试图用str（）创建一个字符串，但仍然会收到此错误：

    ProgrammingError: (ProgrammingError) operator does not exist: double precision ~~ unknown
LINE 3: WHERE markers.lat LIKE '%%' AND markers.lng LIKE '%%' ORDER ...
                          ^
HINT:  No operator matches the given name and argument type(s). You might need to add explicit type casts.
 'SELECT markers.id AS markers_id, markers.type AS markers_type, markers.name AS markers_name, markers.location AS markers_location, markers.lat AS markers_lat, markers.lng AS markers_lng, markers.icon AS markers_icon, markers.message AS markers_message, markers.date AS markers_date, markers.place_id AS markers_place_id, markers.owner AS markers_owner \nFROM markers \nWHERE markers.lat LIKE %(lat_1)s AND markers.lng LIKE %(lng_1)s ORDER BY random() \n LIMIT %(param_1)s' {'lng_1': '%%', 'param_1': 7, 'lat_1': '%%'}

出了什么问题？ sqlalchemy func模块有一种查询浮点列为字符串的方法吗？我该如何解决？谢谢！

p.s我正在使用postgresql

Answer 1

您需要将float转换为字符串

JOIN

SQLalchemy - 对于float列的查询

1 个答案: