Question

我一直在学习使用sqlite3和python。现在，我有一个功能，它会在互联网上查找该词的定义。然后我尝试将该单词存储在一个表中，将定义存储到另一个表中，并通过外键链接在一起。

像这样：

#! /usr/bin/env python
import mechanize
from BeautifulSoup import BeautifulSoup
import sys
import sqlite3

def dictionary(word):
    br = mechanize.Browser()
    response = br.open('http://www.dictionary.reference.com')
    br.select_form(nr=0)
    br.form['q'] = word 
    br.submit()
    definition = BeautifulSoup(br.response().read())
    trans = definition.findAll('td',{'class':'td3n2'})
    fin = [i.text for i in trans]
    query = {}
    word_count = 1
    def_count = 1
    for i in fin: 
        query[fin.index(i)] = i
    con = sqlite3.connect('vocab.db')
    with con:
        spot = con.cursor()
        spot.execute("SELECT * FROM Words")
        rows = spot.fetchall()
        for row in rows:
            word_count += 1
        spot.execute("INSERT INTO Words VALUES(?,?)", word_count,word)
        spot.execute("SELECT * FROM Definitions")
        rows = spot.fetchall()
        for row in rows:
            def_count += 1
        for q in query:
            spot.execute("INSERT INTO Definitions VALUES(?,?,?)", def_count,q,word_count)
    return query

print dictionary(sys.argv[1])

当我运行它时：

./database_trial.py 'pass'

这是错误消息：

Traceback (most recent call last):
  File "./database_trial.py", line 37, in <module>
    print dictionary(sys.argv[1])  
  File "./database_trial.py", line 28, in dictionary
    spot.execute("INSERT INTO Words VALUES(?,?)", word_count,word)
TypeError: function takes at most 2 arguments (3 given)

在函数内部我只有两个参数被传递给'Words'表，但消息说有三个？

spot.execute("INSERT INTO Words VALUES(?,?)", word_count,word)

我以为我可能会搞乱sys.argv。所以我经历了这一行并改为：

spot.execute("INSERT INTO Words VALUES(?,?)", word_count, sys.argv[1])

我的错误信息仍然有相同的结果吗？

Answer 1

spot.execute("INSERT INTO Words VALUES(?,?)", word_count,word)

将三个参数传递给方法spot.execute：SQL字符串，变量word_count和变量word。我怀疑要输入数据库的值需要包含在一个元组中以形成一个参数：

spot.execute("INSERT INTO Words VALUES(?,?)", (word_count,word))

Answer 2

execute只需要两个参数;第二个是要在准备好的SQL语句中使用的所有值的tuple。所以，而不是

spot.execute("INSERT INTO Words VALUES(?,?)", word_count,word)

将所有值包装在元组中：

spot.execute("INSERT INTO Words VALUES(?,?)", (word_count, word) )
#                                             ^                ^

插入sqlite3值时Python TypeError？

2 个答案: