Question

我正在尝试使用MySQLdb查询我的数据库，但是当我发送带有参数的查询时，我得到click_button "submit", wait: 10。我认为它与查询中的TypeError: not all arguments converted during string formatting有关。如何解决此错误？

%s：

Main.py

from flask import Flask, request from app.config import DB from app.items.items import ItemsAPI app = Flask(__name__) db = DB() app.register_blueprint(ItemsAPI) @app.route('/home') def hello_world(): return "Welcome to Omnimoda." @app.route('/dbtest', methods=['GET']) def hello_database(): q_sql = "SELECT SCHEMA_NAME FROM INFORMATION_SCHEMA.SCHEMATA WHERE SCHEMA_NAME = '%s'" a_sql = "omnimoda" test_request = db.query(q_sql, a_sql) result_request = test_request.fetchall() if (result_request is None): return "Database does not exist." else: return "Database exists."：

Items.py

from flask import Flask, request, jsonify, json, Blueprint from app.config import DB ItemsAPI = Blueprint('ItemsAPI', __name__) db = DB() @ItemsAPI.route('/items/listbycode', methods=['POST']) def get_item_by_code(): value = request.form['value'] q_list_all = "SELECT * FROM item_info WHERE item_code = '%s'" print q_list_all a_list_all = (value) items_request = db.query(q_list_all, a_list_all) json_output = json.dumps(items_request.fetchall()) return json_output：

config.py

回溯：

from flask import Flask
import MySQLdb

class DB:
    conn = None

    def connect(self):
        self.conn = MySQLdb.connect(host="localhost", user="user", passwd="passwd", db="test_dbase")
        self.conn.autocommit(True)

    def query(self, sql, values):
        try:
            print values
            cursor = self.conn.cursor()
            cursor.execute(sql)
        except (AttributeError, MySQLdb.OperationalError):
            self.connect()
            cursor = self.conn.cursor()
            cursor.execute(sql)
        return cursor

Answer 1

cursor.execute期望列表作为其第二个参数

q_list_all = "SELECT * FROM item_info WHERE item_code = '%s'"
print q_list_all
a_list_all = (value,) #the comma makes it a list not the parens
items_request = db.query(q_list_all, a_list_all)

当你传递一个字符串

cur.execute(qry,"MyArg") # =becomes==> cur.execute(qry,["M","y","A","r","g"])

在某种程度上不相关的说明中，您应该考虑使用像sqlalchemy这样的ORM

Answer 2

(value)不是一个元组，它只是一个字符串。字符串是其字符的可迭代。所以实际上它好像你将输入字段中的字符列表传递给SQL语句，后者只有一个参数的空间。

改为使用(value,)。

执行数据库查询会出现“TypeError：并非所有在字符串格式化过程中转换的参数”

2 个答案: