有没有办法根据列表的长度设置 SQL 查询中的变量数量？

Question

我正在尝试根据用户的选择从数据库中获取每月值并将它们可视化。 我有复选框，如下所示；

Checkboxes I used

为了根据用户的选择获取每月销售数字，我从复选框中获取值并创建一个新列表，其中仅包含不等于零的值。之后，我编写了一个 Select 查询，其中特定列具有列表中的任何值。但是用户只能选择 1 个值或 3 个值或其他任何值，我的 sql 查询必须根据它进行更改。如果用户选择 1 个值，我必须在我的查询中只使用 1 个“%s”，如果他们选择 5 个值，我必须使用其中的 5 个。所以我创建了一堆 if 函数，其中条件是列表的长度。有没有办法根据列表的长度来安排sql查询中的变量数量？

def plot(self):
        self.listo=[]
        for val in self.lili:
        
        # self.lili is a list that has all of the checkboxes value in it. Unchecked box values is 0 for all.Checked box values is changing based on month.
        
            val=val.get()
            if val !=0:# I created a empty list and add all the checked values in it.
                self.listo.append(val)   
            else:
                pass
        self.tryn=len(self.listo)# I get the lenght of checked checkboxes.
        
        if self.tryn==0:#If anything is selected it's an error.
            messagebox.showerror("Error", "You have to choose at least one")
        if self.tryn==1:##If 1 values is selected use this query with 1 variable.
        
            self.cursor.execute("SELECT SUM(current_sales) FROM targets WHERE nameofmonth=(%s)",(self.listo[0],))
            self.current_sales1=self.cursor.fetchall()[0][0]
            self.cursor.execute("SELECT SUM(target_sales) FROM targets WHERE nameofmonth=(%s)",(self.listo[0],))
            self.target_sales1=self.cursor.fetchall()[0][0]
            self.show_plot()
        if self.tryn==2:##If 2 values is selected use this query with 2 variable.
            query=("SELECT SUM(target_sales) FROM targets WHERE (nameofmonth=(%s) OR nameofmonth=(%s))")
            self.cursor.execute(query,self.listo)
            self.target_sales1=self.cursor.fetchall()[0][0]
            query2=("SELECT SUM(current_sales) FROM targets WHERE (nameofmonth=(%s) OR nameofmonth=(%s))")
            self.cursor.execute(query2,self.listo)
            self.current_sales1=self.cursor.fetchall()[0][0]
            self.show_plot()
        if self.tryn==3:
            query=("SELECT SUM(target_sales) FROM targets WHERE (nameofmonth=(%s) OR nameofmonth=(%s)) OR nameofmonth=(%s)")
            self.cursor.execute(query,self.listo)
            self.target_sales1=self.cursor.fetchall()[0][0]
            query2=("SELECT SUM(current_sales) FROM targets WHERE (nameofmonth=(%s) OR nameofmonth=(%s)) OR nameofmonth=(%s)")
            self.cursor.execute(query2,self.listo)
            self.current_sales1=self.cursor.fetchall()[0][0]
            self.show_plot()

Answer 1

我找到了一个更好的方法来做到这一点。 我创建了一个字符串并将其与包含选中复选框值的列表的长度相乘。

query="WHERE "+"nameofmonth=(%s) OR "*self.tryn 

为了去掉末尾多余的 OR 和空格；

query=query[:-3]

我只是使用这个变量格式化了我的查询。

你可以在这里看到完整的功能和解释；

def plot(self):
            self.listo=[]
            for val in self.lili:
            
            # self.lili is a list that has all of the checkboxes value in it. Unchecked box values is 0 for all.Checked box values is changing based on month.
            
                val=val.get()
                if val !=0:# I created a empty list and add all the checked values in it.
                    self.listo.append(val)   
                else:
                    pass
            self.tryn=len(self.listo)# I get the lenght of checked checkboxes.
            
            query="WHERE "+"nameofmonth=(%s) OR "*self.tryn 
            #Creating a string variable for my query condition and multiplying it with lenght of the check box values.
            #For example if 3 boxes checked by user we get something like that "WHERE nameofmonth=(%s) OR nameofmonth=(%s) OR nameofmonth=(%s) OR "
            query=query[:-3]
            #Getting rid of the extra OR and space at the end. 
            query2="WHERE "+"nameofmonth=(%s) OR "*self.tryn
            #Couldnt use one query for 2 execute function so i just created another one and it worked xd
            query2=query2[:-3]
            
            query=("SELECT SUM(current_sales) FROM targets {}".format(query))
            #Using this query i get this output (for 3 checked checkboxes)
            #("SELECT SUM(current_sales) FROM targets WHERE nameofmonth=(%s) OR nameofmonth=(%s) OR nameofmonth=(%s))
            self.cursor.execute(query,self.listo)
            #Executing the query by using the list that has the values from checkboxes where values are not equal to zero.
            self.current_sales1=self.cursor.fetchall()[0][0]
            #Getting the SUM of the column i want in INT type.