import pandas as pd
import sqlite3
# 利用pandas讀取數(shù)據(jù)
student_df=pd.read_csv("./Dataset/student_grades.csv",encoding='utf-8-sig')

# 創(chuàng)建學(xué)生成績數(shù)據(jù)庫
conn=sqlite3.connect("./Database/Student_grade.db")
## 創(chuàng)建游標(biāo)
cursor=conn.cursor()
## 創(chuàng)建成績表
try:
    # 判斷表是否存在, 存在則先刪除
    dropif_sql='Drop TABLE IF EXISTS student_grades;'
    create_sql='''
        CREATE TABLE student_grades
        (
            studentID varchar(64),
            studentName varchar(64),
            scoreEnglish float(64),
            scoreChinese float(64),
            scoreMath float(64)
        )
    '''
    cursor.execute(dropif_sql)
    cursor.execute(create_sql)
except:
    print("Create table failed!")

# 將學(xué)生信息存入數(shù)據(jù)庫
for i in range(student_df.shape[0]):
    print(student_df.loc[i,:].to_list())
    # 插入語句
    insert_sql='''
        INSERT INTO student_grades(studentID, studentName, scoreEnglish, scoreChinese, scoreMath)
        Values('%s','%s','%f','%f','%f')'''%(
            str(student_df.loc[i,'StudentID']),
            str(student_df.loc[i,'name']),
            student_df.loc[i,'english'],
            student_df.loc[i,'chinese'],
            student_df.loc[i,'math'],
        )
    # 執(zhí)行語句
    cursor.execute(insert_sql)
    # 事物提交
    conn.commit()

# 錄入李四的數(shù)學(xué)成績
grade_LiSi=70
# 更新語句
update_sql='UPDATE student_grades SET scoreMath={} WHERE studentID=10002'.format(grade_LiSi)
# 執(zhí)行語句
cursor.execute(update_sql)
# 事物提交
conn.commit()

# 查詢錄入李四成績后的信息
select_sql='SELECT * FROM student_grades;'
# 執(zhí)行語句
results=cursor.execute(select_sql)
# 遍歷輸出
for info in results.fetchall():
    print(info)

# 更新王五的數(shù)學(xué)成績
grade_WangWu=85
# 更新語句
update_sql='UPDATE student_grades SET scoreMath={} WHERE studentID=10003'.format(grade_WangWu)
# 執(zhí)行語句
cursor.execute(update_sql)
# 事物提交
conn.commit()

# 查詢王五的成績
select_sql='SELECT * FROM student_grades WHERE studentID=10003;'
# 執(zhí)行語句
results=cursor.execute(select_sql)
# 遍歷輸出
for info in results.fetchall():
    print(info)

# 查詢數(shù)據(jù)
select_sql='SELECT * FROM student_grades;'
# 執(zhí)行語句
results=cursor.execute(select_sql)
# 計算各科平均分以及總分排名
english_lst=[]
chinese_lst=[]
math_lst=[]
total_dct={}
for info in results.fetchall():
    english_lst.append(info[2])
    chinese_lst.append(info[3])
    math_lst.append(info[4])
    total_dct[info[1]]=sum(info[2:])

# 計算平均分的函數(shù)
def average_score(lst):
    return round(sum(lst)/len(lst),2)

# 輸出結(jié)果
print("英語平均分為:", average_score(english_lst))
print("語文平均分為:", average_score(chinese_lst))
print("數(shù)學(xué)平均分為:", average_score(math_lst))
print("總成績排名為:", sorted(total_dct.items(), key=lambda x:x[1], reverse=True))