Python Flask - WTF SelectField 数据导致错误_mysql_exceptions.ProgrammingError

Question

当我尝试将数据从 SelectField 添加到 MySQL 数据库时，会发生此错误：

_mysql_exceptions.ProgrammingError _mysql_exceptions.ProgrammingError: 在字符串格式化期间并非所有参数都转换了

我的代码：

class ContentForm(Form):
category = SelectField("Category: ",choices=[('DataScience','Data Science'), ('ComputerProgramming', 'Computer Programming'),('DigitalMarketing','Digital Marketing'),('Other','Other')], validators=[validators.DataRequired()])
title = StringField("Title: ",validators=[validators.length(min= 5, max = 100), validators.DataRequired()])
content = TextAreaField("Content: ", validators=[validators.length(min = 10), validators.DataRequired()])

@app.route("/addcontent", methods=["GET","POST"])
@login_required
def addcontent():
form = ContentForm(request.form)
if request.method == "POST" and form.validate():
    category = form.category.data
    title = form.title.data
    content = form.content.data
    cursor = mysql.connection.cursor()
    query = "INSERT INTO contents (author, category, title,content) VALUES(%s,%s,%s)"
    cursor.execute(query, (session["username"], category, title, content))
    mysql.connection.commit()
    cursor.close()
    flash("Your content have added successfully. Thanks your contributions.", 'success')
    return redirect(url_for("dashboard"))
return render_template("addcontent.html", form = form)

HTML：

{% from "includes/_formhelpers.html" import render_field %}

<form method="post">

        {{ render_field(form.category, class="form-control", style = "width: 40% !important") }}
        {{ render_field(form.title, class="form-control", style = "width: 40% !important") }}
        {{ render_field(form.content, class="form-control", style = "height: 300px !important") }}

    <button type="submit" class="btn btn-primary btn-lg">Add Content</button>   

我该如何解决这个问题？

Answer 1

你的问题来自于

cursor.execute(query, (session["username"], category, title, content))

您应该以身份访问会话

session.get('username')

尝试使用一些字符串执行查询以进行测试，看看它是否会成功执行，例如：

cursor.execute(query, 'myName', category, title, content))