将csv文件导入sqlite表

时间:2016-12-13 02:28:04

标签: python sql sqlite csv

我正在尝试将我的csv文件导入到我的表中。我按照here找到了类似的步骤,但是我收到了错误:

test.csv

"a",1,1
"b",2,2
"c",3,3

错误:

Traceback (most recent call last):
  File "C:/Users/Sam/Desktop/big data/workspace/yelpdatabase.py", line 19, in <module>
    to_db = [(i['letter'], i['num1'], i['num2']) for i in dr]
  File "C:/Users/Sam/Desktop/big data/workspace/yelpdatabase.py", line 19, in <listcomp>
    to_db = [(i['letter'], i['num1'], i['num2']) for i in dr]
KeyError: 'letter'

代码:

import csv
import sqlite3

#Create The Database
connection = sqlite3.connect('test.db')

#create cursor
cursor = connection.cursor()

#Create table
cursor.execute('DROP TABLE IF EXISTS testtable')
cursor.execute('CREATE TABLE testtable ( letter text, num1 int, num2, int)')

#Load the CSV file into CSV reader
path = r"C:\Users\Sam\Desktop\big data\workspace\test.csv"
with open(path,'r') as fin: # `with` statement available in 2.5+
    # csv.DictReader uses first line in file for column headings by default
    dr = csv.DictReader(fin)  # comma is default delimiter
    to_db = [(i['letter'], i['num1'], i['num2']) for i in dr]

cursor.executemany("INSERT INTO t (letter, num1, num2) VALUES (?, ?, ?);", to_db)

#commit changes, and close the connection
connection.commit()
connection.close()

编辑:我上传了test.csv文件

1 个答案:

答案 0 :(得分:2)

如果不查看CSV,很难确定是什么问题,但“KeyError”表示DictReader生成的字典没有名为“letter”的键。

仔细检查CSV的第一行是否有“字母”。例如,如果我的CSV看起来像这样:

  

头像1,HEAD2,头像3

     

1,2,3

然后提取数据的正确行将是:

to_db = [(i["head1"], i["head2"], i["head3"]) for i in dr]

注意 - 键区分大小写,因此在上面的示例中,“head1”有效,但“Head1”会生成KeyError。

编辑:感谢您发布CSV。问题似乎是您没有标题行,因此DictReader获取字段名["a","1","1"](您可以通过调用dr.fieldnames来检查)。

要使代码无需修改CSV,您可以将DictReader行更改为:

csv.DictReader(fin, ["letter", "num1", "num2"])

这将手动将标题“letter”,“num1”和“num2”分配给您的三列。然后你可以这样做:

to_db = [(i["letter"], i["num1"], i["num2"]) for i in dr]