INSERT INTO via SQLAlchemy/MySQL 在使用参数执行时不起作用
INSERT INTO via SQLAlchemy/MySQL doesn't work when executed with parameters
我有一个带有 POST 方法和其他方法的基本烧瓶 API。这是针对 MySQL 数据库的 运行 查询。这是代码的相关部分：
from flask import Flask, Response, request
from sqlalchemy.sql import text
from flask.views import MethodView
import json
class BooksAPI(MethodView):
def post(self):
sql = text("INSERT INTO books (title, year_written, author) VALUES (%s, %s, %s)")
title = request.form['title']
year_written = request.form['year']
author = request.form['author']
db.session.execute(sql, (title, year_written, author))
db.session.commit()
return Response(f'Successfully inserted book with title "{title}" by "{author}" of "{year_written}".', status=201, mimetype='application/json')
# Omitting other methods
def route(app):
view = BooksAPI.as_view('books_api')
app.add_url_rule('/api/v1/book',
view_func=view,
methods=['POST',])
# Omitting additional code for initializing and running the API.
该方法预计会在通过 cURL 请求时插入一本书：
curl -X POST 127.0.0.1:80/api/v1/book -d title="titleexample" -d author="authorexample" -d year=1234
但是，我得到以下回溯：
* Serving Flask app 'app' (lazy loading)
* Environment: production
WARNING: This is a development server. Do not use it in a production deployment.
Use a production WSGI server instead.
* Debug mode: off
* Running on all addresses.
WARNING: This is a development server. Do not use it in a production deployment.
* Running on http://172.17.0.2:80/ (Press CTRL+C to quit)
[2022-05-11 12:08:43,126] ERROR in app: Exception on /api/v1/book [POST]
Traceback (most recent call last):
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 1819, in _execute_context
self.dialect.do_execute(
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/default.py", line 732, in do_execute
cursor.execute(statement, parameters)
File "/usr/local/lib/python3.10/site-packages/pymysql/cursors.py", line 148, in execute
result = self._query(query)
File "/usr/local/lib/python3.10/site-packages/pymysql/cursors.py", line 310, in _query
conn.query(q)
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 548, in query
self._affected_rows = self._read_query_result(unbuffered=unbuffered)
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 775, in _read_query_result
result.read()
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 1156, in read
first_packet = self.connection._read_packet()
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 725, in _read_packet
packet.raise_for_error()
File "/usr/local/lib/python3.10/site-packages/pymysql/protocol.py", line 221, in raise_for_error
err.raise_mysql_exception(self._data)
File "/usr/local/lib/python3.10/site-packages/pymysql/err.py", line 143, in raise_mysql_exception
raise errorclass(errno, errval)
pymysql.err.ProgrammingError: (1064, "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '%s, %s, %s)' at line 1")
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/usr/local/lib/python3.10/site-packages/flask/app.py", line 2073, in wsgi_app
response = self.full_dispatch_request()
File "/usr/local/lib/python3.10/site-packages/flask/app.py", line 1518, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/usr/local/lib/python3.10/site-packages/flask/app.py", line 1516, in full_dispatch_request
rv = self.dispatch_request()
File "/usr/local/lib/python3.10/site-packages/flask/app.py", line 1502, in dispatch_request
return self.ensure_sync(self.view_functions[rule.endpoint])(**req.view_args)
File "/usr/local/lib/python3.10/site-packages/flask/views.py", line 84, in view
return current_app.ensure_sync(self.dispatch_request)(*args, **kwargs)
File "/usr/local/lib/python3.10/site-packages/flask/views.py", line 158, in dispatch_request
return current_app.ensure_sync(meth)(*args, **kwargs)
File "/app/./src/app.py", line 38, in post
db.session.execute(sql, (title, year_written, author))
File "<string>", line 2, in execute
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/orm/session.py", line 1696, in execute
result = conn._execute_20(statement, params or {}, execution_options)
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 1631, in _execute_20
return meth(self, args_10style, kwargs_10style, execution_options)
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/sql/elements.py", line 325, in _execute_on_connection
return connection._execute_clauseelement(
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 1498, in _execute_clauseelement
ret = self._execute_context(
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 1862, in _execute_context
self._handle_dbapi_exception(
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 2043, in _handle_dbapi_exception
util.raise_(
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/util/compat.py", line 207, in raise_
raise exception
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 1819, in _execute_context
self.dialect.do_execute(
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/default.py", line 732, in do_execute
cursor.execute(statement, parameters)
File "/usr/local/lib/python3.10/site-packages/pymysql/cursors.py", line 148, in execute
result = self._query(query)
File "/usr/local/lib/python3.10/site-packages/pymysql/cursors.py", line 310, in _query
conn.query(q)
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 548, in query
self._affected_rows = self._read_query_result(unbuffered=unbuffered)
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 775, in _read_query_result
result.read()
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 1156, in read
first_packet = self.connection._read_packet()
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 725, in _read_packet
packet.raise_for_error()
File "/usr/local/lib/python3.10/site-packages/pymysql/protocol.py", line 221, in raise_for_error
err.raise_mysql_exception(self._data)
File "/usr/local/lib/python3.10/site-packages/pymysql/err.py", line 143, in raise_mysql_exception
raise errorclass(errno, errval)
sqlalchemy.exc.ProgrammingError: (pymysql.err.ProgrammingError) (1064, "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '%s, %s, %s)' at line 1")
[SQL: INSERT INTO books (title, year_written, author) VALUES (%%s, %%s, %%s)]
(Background on this error at: https://sqlalche.me/e/14/f405)
我尝试将我的值硬编码到该方法中并且它有效，我通过 GET 请求确认：
class BooksAPI(MethodView):
def post(self):
sql = text("INSERT INTO books (title, year_written, author) VALUES ('titleexample', 1234, 'authorexample')")
title = request.form['title']
year_written = request.form['year']
author = request.form['author']
db.session.execute(sql)
db.session.commit()
return Response(f'Successfully inserted book with title "{title}" by "{author}" of "{year_written}".', status=201, mimetype='application/json')
所以可能我的参数没有写对。我做错了什么？
您的值似乎没有进入导致问题的字符串的 %s 部分。
From the documentation 似乎您应该更改在文本语句中标记变量的方式，以便它们更直接地联系在一起。根据我读到的内容，这样设置可能会起作用：
def post(self):
sql = text("INSERT INTO books (title, year_written, author) VALUES (:title, :year, :author)")
title = request.form['title']
year_written = request.form['year']
author = request.form['author']
db.session.execute(sql, {"title": title, "year": year_written, "author": author})
db.session.commit()
return Response(f'Successfully inserted book with title "{title}" by "{author}" of "{year_written}".', status=201, mimetype='application/json')
不过我还没有测试过，所以可能会有拼写错误等。希望这对您有所帮助！
我有一个带有 POST 方法和其他方法的基本烧瓶 API。这是针对 MySQL 数据库的 运行 查询。这是代码的相关部分：
from flask import Flask, Response, request
from sqlalchemy.sql import text
from flask.views import MethodView
import json
class BooksAPI(MethodView):
def post(self):
sql = text("INSERT INTO books (title, year_written, author) VALUES (%s, %s, %s)")
title = request.form['title']
year_written = request.form['year']
author = request.form['author']
db.session.execute(sql, (title, year_written, author))
db.session.commit()
return Response(f'Successfully inserted book with title "{title}" by "{author}" of "{year_written}".', status=201, mimetype='application/json')
# Omitting other methods
def route(app):
view = BooksAPI.as_view('books_api')
app.add_url_rule('/api/v1/book',
view_func=view,
methods=['POST',])
# Omitting additional code for initializing and running the API.
该方法预计会在通过 cURL 请求时插入一本书：
curl -X POST 127.0.0.1:80/api/v1/book -d title="titleexample" -d author="authorexample" -d year=1234
但是，我得到以下回溯：
* Serving Flask app 'app' (lazy loading)
* Environment: production
WARNING: This is a development server. Do not use it in a production deployment.
Use a production WSGI server instead.
* Debug mode: off
* Running on all addresses.
WARNING: This is a development server. Do not use it in a production deployment.
* Running on http://172.17.0.2:80/ (Press CTRL+C to quit)
[2022-05-11 12:08:43,126] ERROR in app: Exception on /api/v1/book [POST]
Traceback (most recent call last):
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 1819, in _execute_context
self.dialect.do_execute(
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/default.py", line 732, in do_execute
cursor.execute(statement, parameters)
File "/usr/local/lib/python3.10/site-packages/pymysql/cursors.py", line 148, in execute
result = self._query(query)
File "/usr/local/lib/python3.10/site-packages/pymysql/cursors.py", line 310, in _query
conn.query(q)
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 548, in query
self._affected_rows = self._read_query_result(unbuffered=unbuffered)
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 775, in _read_query_result
result.read()
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 1156, in read
first_packet = self.connection._read_packet()
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 725, in _read_packet
packet.raise_for_error()
File "/usr/local/lib/python3.10/site-packages/pymysql/protocol.py", line 221, in raise_for_error
err.raise_mysql_exception(self._data)
File "/usr/local/lib/python3.10/site-packages/pymysql/err.py", line 143, in raise_mysql_exception
raise errorclass(errno, errval)
pymysql.err.ProgrammingError: (1064, "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '%s, %s, %s)' at line 1")
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/usr/local/lib/python3.10/site-packages/flask/app.py", line 2073, in wsgi_app
response = self.full_dispatch_request()
File "/usr/local/lib/python3.10/site-packages/flask/app.py", line 1518, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/usr/local/lib/python3.10/site-packages/flask/app.py", line 1516, in full_dispatch_request
rv = self.dispatch_request()
File "/usr/local/lib/python3.10/site-packages/flask/app.py", line 1502, in dispatch_request
return self.ensure_sync(self.view_functions[rule.endpoint])(**req.view_args)
File "/usr/local/lib/python3.10/site-packages/flask/views.py", line 84, in view
return current_app.ensure_sync(self.dispatch_request)(*args, **kwargs)
File "/usr/local/lib/python3.10/site-packages/flask/views.py", line 158, in dispatch_request
return current_app.ensure_sync(meth)(*args, **kwargs)
File "/app/./src/app.py", line 38, in post
db.session.execute(sql, (title, year_written, author))
File "<string>", line 2, in execute
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/orm/session.py", line 1696, in execute
result = conn._execute_20(statement, params or {}, execution_options)
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 1631, in _execute_20
return meth(self, args_10style, kwargs_10style, execution_options)
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/sql/elements.py", line 325, in _execute_on_connection
return connection._execute_clauseelement(
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 1498, in _execute_clauseelement
ret = self._execute_context(
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 1862, in _execute_context
self._handle_dbapi_exception(
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 2043, in _handle_dbapi_exception
util.raise_(
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/util/compat.py", line 207, in raise_
raise exception
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/base.py", line 1819, in _execute_context
self.dialect.do_execute(
File "/usr/local/lib/python3.10/site-packages/sqlalchemy/engine/default.py", line 732, in do_execute
cursor.execute(statement, parameters)
File "/usr/local/lib/python3.10/site-packages/pymysql/cursors.py", line 148, in execute
result = self._query(query)
File "/usr/local/lib/python3.10/site-packages/pymysql/cursors.py", line 310, in _query
conn.query(q)
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 548, in query
self._affected_rows = self._read_query_result(unbuffered=unbuffered)
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 775, in _read_query_result
result.read()
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 1156, in read
first_packet = self.connection._read_packet()
File "/usr/local/lib/python3.10/site-packages/pymysql/connections.py", line 725, in _read_packet
packet.raise_for_error()
File "/usr/local/lib/python3.10/site-packages/pymysql/protocol.py", line 221, in raise_for_error
err.raise_mysql_exception(self._data)
File "/usr/local/lib/python3.10/site-packages/pymysql/err.py", line 143, in raise_mysql_exception
raise errorclass(errno, errval)
sqlalchemy.exc.ProgrammingError: (pymysql.err.ProgrammingError) (1064, "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '%s, %s, %s)' at line 1")
[SQL: INSERT INTO books (title, year_written, author) VALUES (%%s, %%s, %%s)]
(Background on this error at: https://sqlalche.me/e/14/f405)
我尝试将我的值硬编码到该方法中并且它有效，我通过 GET 请求确认：
class BooksAPI(MethodView):
def post(self):
sql = text("INSERT INTO books (title, year_written, author) VALUES ('titleexample', 1234, 'authorexample')")
title = request.form['title']
year_written = request.form['year']
author = request.form['author']
db.session.execute(sql)
db.session.commit()
return Response(f'Successfully inserted book with title "{title}" by "{author}" of "{year_written}".', status=201, mimetype='application/json')
所以可能我的参数没有写对。我做错了什么？
您的值似乎没有进入导致问题的字符串的 %s 部分。
From the documentation 似乎您应该更改在文本语句中标记变量的方式，以便它们更直接地联系在一起。根据我读到的内容，这样设置可能会起作用：
def post(self):
sql = text("INSERT INTO books (title, year_written, author) VALUES (:title, :year, :author)")
title = request.form['title']
year_written = request.form['year']
author = request.form['author']
db.session.execute(sql, {"title": title, "year": year_written, "author": author})
db.session.commit()
return Response(f'Successfully inserted book with title "{title}" by "{author}" of "{year_written}".', status=201, mimetype='application/json')
不过我还没有测试过，所以可能会有拼写错误等。希望这对您有所帮助！