使用 SQL 和 Python (CS50 PSET7)

Question

这个程序有两个部分。

1. 在 import.py 中，编写从 CSV 电子表格导入数据的程序。 CSV 电子表格包含全名、出生、年份，我想将全名分隔为“名字”、“中间名”、“姓氏”。我的程序如下：

import.py

from csv import reader
from sys import argv, exit
from cs50 import SQL
import csv
import sys

# check command line arguments
if len(sys.argv) != 2:
    print(f"Usage: import.py .csv")
    exit(1)

if not argv[1].endswith(".csv"):
    print(f"Usage: import.py .csv 3 arg")
    exit(1)

# variables
db = SQL("sqlite:///students.db")

total = 0
first = []
middle = []
last = []
house = []
birth = []

with open(argv[1], 'r') as csvfile:
    data = csv.reader(csvfile)

    for row in data:
        names = row[0]
        house = row[1]
        birth = row[2]
    total = total + 1

# split names

    if len(names) == 2:
        first.append(names[0])
        middle.append('None')
        last.append(names[1])

    if len(names) == 3:
        first.append(names[0])
        middle.append(middle[2])
        last.append(names[2])

    for i in range(total - 1):
        db.execute("INSERT INTO students (first, middle, last, house, birth) VALUES (?, ?, ?, ?, ?)", first[i], middle[i], last[i], house[i], birth[i])

1. 第二部分 roster.py 的任务是编写一个程序，该程序按字母顺序打印给定房子的学生列表。

例如对于

$ python roster.py Gryffindor

程序应该返回例如

Hermione Jean Granger, born 1979
Harry James Potter, born 1980
Ginevra Molly Weasley, born 1981
Ronald Bilius Weasley, born 1980

我的代码如下：

roster.py

from csv import reader
from sys import argv, exit
from cs50 import SQL
import sys

db = SQL("sqlite:///students.db")

# check command line arguments
if len(sys.argv) != 2:
    print(f"Usage: python roster.py house")
    exit(1)

house = sys.argv[1]

# if sys.argv[1].lower() != "slytherin" or sys.argv[1].lower() != "gryffindor" or sys.argv[1].lower() != "ravenclaw" or sys.argv[1].lower() != "hufflepuff":
  #  print("choose a house!")
   # exit(1)

rows = db.execute('SELECT * FROM students WHERE house = (?) ORDER BY last, first', sys.argv[1])

for row in rows:
    print(row['first'],end=" ")

    if row["middle"] != 'None':
        print(row['middle'],end=" ")

    print(row['last'],end=", ")
    print("born ", row['birth'])

我被困了很长时间，不明白为什么代码没有打印出名称！非常感谢您的帮助！

Answer 1

import.py 存在三个问题， 首先total 的缩进错误， 其次，您没有附加到列表，而是覆盖它， 最后，您的 create 语句不正确。

看看这是否有帮助 -

total = 0
first = []
middle = []
last = []
house = []
birth = []

with open(argv[1], 'r') as csvfile:
    data = csv.reader(csvfile)

    for row in data:
        names = row[0].split()
        house = row[1]
        birth = row[2]
        total = total + 1

        # split names

        if len(names) == 2:
            first.append(names[0])
            middle.append('None')
            last.append(names[1])
        
        if len(names) == 3:
            first.append(names[0])
                middle .append(names[1])
                last.append(names[2])

db.execute("CREATE TABLE students (first char(100), middle char(100), last char(100), house char(100), birth char(100))")

for i in range(total):
        db.execute("INSERT INTO students (first, middle, last, house, birth) VALUES (?, ?, ?, ?, ?)", first[i], middle[i], last[i], house[i], birth[i])

如您所见，我已将 CREATE 和 INSERT 分开。由于我不知道出生的数据类型，我假设它是 CHAR，请根据您的需要进行修改。