Question

我有大量的文字，我正在尝试计算其中的所有单词以获取其频率。将字典保存在内存中太大了所以我使用sqlite来完成这项任务。我编写了一个Database类，并将该词用作主键，因为它应该是唯一的。

在这个过程的某个地方，它失败了，因为“频率”这个词试图加两次。我不知道为什么会发生这种情况，因为还有许多其他常用词已经被计算过两次......这是我的两个文件....

dbmaker.py

import sqlite3
import sys



class Database():
    '''Creates an object with method for adding and checking words against an sqlite database'''

def __init__(self):
    self.dbname = raw_input('What will be the name of this database: ')
    self.table1 = 'words'
    self.column1 = 'word_name'
    self.column1t = 'TEXT'
    self.column2 = 'frequency'
    self.column2t = 'INTEGER'
    self.conn = sqlite3.connect(self.dbname)
    self.c = self.conn.cursor()
    self.c.execute('CREATE TABLE {tn} ({nf} {ft} PRIMARY KEY)'.\
        format(tn=self.table1, nf=self.column1, ft=self.column1t))
    self.c.execute('ALTER TABLE {tn} ADD COLUMN {cn} {ct}'.\
        format(tn=self.table1, cn=self.column2, ct=self.column2t))
    self.conn.commit()
    self.checkfile = open('check.txt', 'w+')



def check_word(self, word_name):
    exist = self.c.execute('SELECT * FROM {tn} WHERE {cn}="{wn}"'.\
        format(tn=self.table1, cn=self.column1, wn=word_name))

    exist = self.c.fetchall()
    if exist:
        new_freq = exist[0][1] + 1
        self.c.execute("UPDATE {tn} SET {c2n}={en} WHERE {c1n}='{word}'".\
            format(tn=self.table1, c2n=self.column2, en=new_freq, c1n=self.column1, word=word_name))
        return True
    else:
        return False



def add_word(self, word_name, frequency=1):
    self.checkfile.write('%s\n' % word_name)
    self.c.execute('INSERT INTO {tn} ({c1n}, {c2n}) VALUES ("{wn}", {f})'.\
        format(tn=self.table1, c1n=self.column1, c2n=self.column2, wn=word_name, f=frequency))

crunch.py

import sys
import operator
from dbmaker import Database

db = Database()
infile = open(sys.argv[1])

for line in infile:
    line = line.split()
    for word in line:
        word=word.lower()
        if not db.check_word(word):
            db.add_word(word)

db.conn.commit（） db.conn.close（）

这是我的错误：

Traceback (most recent call last):
  File "crunch.py", line 13, in <module>
    db.add_word(word)
  File "/home/ubuntu/wikicorpus/dbmaker.py", line 44, in add_word
    format(tn=self.table1, c1n=self.column1, c2n=self.column2, wn=word_name, f=frequency))

sqlite3.IntegrityError：UNIQUE约束失败：words.word_name

python和sqlite无法插入违反唯一约束

0 个答案: