>我在python脚本中定义了一个现有的数据库表，每当我尝试在db表中插入一行时，我都会收到一条错误消息，指出"表对象不可调用">
您可以在下面找到我收到的代码和错误消息。任何支持将不胜感激：
engine = create_engine('postgresql://user:pwd@localhost:5432/dbname',
client_encoding='utf8')
metadata = MetaData()
MyTable = Table('target_table', metadata, autoload=True, autoload_with=engine)
Session = sessionmaker()
Session.configure(bind=engine)
session = Session()
:
:
:
def recod_to_db(db_hash):
db_instance = MyTable(**db_hash)
session.add(db_instance)
session.commit()
return
错误信息：
File "myprog.py", line 319, in recod_to_db
db_instance = MyTable(**db_hash)
TypeError: 'Table' object is not callable
这是表格的外观
Table "public.target_table"
Column | Type | Modifiers | Storage | Stats target | Description
-------------------+-----------------------------+--------------------------------------------------------+----------+--------------+-------------
id | integer | not null default nextval('target_table_id_seq'::regclass) | plain | |
carid | integer | | plain | |
triplecode | character varying | | extended | |
lookup | integer | | plain | |
type | character varying | | extended | |
make | character varying | | extended | |
series | character varying | | extended | |
model | character varying | | extended | |
year | integer | | plain | |
fuel | character varying | | extended | |
transmission | character varying | | extended | |
mileage | integer | | plain | |
hp | integer | | plain | |
color | character varying | | extended | |
door | integer | | plain | |
location | character varying | | extended | |
url | character varying | | extended | |
register_date | date | | plain | |
auction_end_time | timestamp without time zone | | plain | |
body_damage | integer | | plain | |
mechanical_damage | integer | | plain | |
target_buy | integer | | plain | |
price | integer | | plain | |
currency | character varying | | extended | |
auctionid | integer | | plain | |
seller | character varying | | extended | |
auction_type | character varying | | extended | |
created_at | timestamp without time zone | not null | plain | |
updated_at | timestamp without time zone | not null | plain | |
estimated_value | integer | | plain | |
Indexes:
"target_table_pkey" PRIMARY KEY, btree (id)
另一种不带auto_map的插入方法是使用表的方法进行插入。文档在这里
insert(dml， values=None， inline=False， **kwargs( 针对此 TableClause 生成一个 insert(( 构造。
例如：
table.insert((.values(name='foo'(
在代码中，它看起来像这样：
def record_to_db(MyTable):
insert_stmnt = MyTable.insert().values(column_name=value_you_want_to_insert)
session.execute(insert_stmnt)
session.commit()
return
理想情况下，您将表定义在app.py以外的单独文件夹中。您还可以使用utils函数来生成会话，然后提交或捕获异常并对其进行回滚。像这样：
def get_db_session_scope(sql_db_session):
session = sql_db_session()
try:
yield session
session.commit()
except:
session.rollback()
raise
finally:
session.close()
那么你的函数将如下所示：
def record_to_db(MyTable):
with get_db_session_scope(db) as db_session:
insert_stmnt =
MyTable.insert().values(column_name=value_you_want_to_insert)
session.execute(insert_stmnt)
return
您可以通过以下方式从app.py获取数据库
from flask_sqlalchemy import SQLAlchemy
db = SQLAlchemy(app)