Question

由于它可以在简单的excel表格上工作，所以我制作了一个可以扼杀程序的程序。

我可以简单地描述我的问题：

也是小时分派器的标头，我已经尝试了header = None和parscols = [“”，“”]，但标头仍不会加入数据库
即使我避免了丢失的数据，excel工作表的值也不会进入数据库。

这是我的代码：

from src.server.connectToDB import get_sql_conn
import pandas as pd


if __name__ == '__main__':
    cursor = get_sql_conn().cursor()
    local_files = 'C:\\Users\\dersimw\\Source\Repos\\nordpoolAnalyse\\data\\2011-3.xlsx'
    excelFile = pd.ExcelFile(local_files)

    ark = ["01", "02", "03", "04", "05", "06", "07", "08", "09", "10", "11", "12", "13", "14", "15",
         "16", "17", "18", "19", "20", "21", "22", "23", "24", "25", "26", "27", "28", "29", "30", "31"]

    for sheets in ark:
        df = excelFile.parse(sheets).head(5)
        print(df.dropna(axis=1, how='all'))
        for key, rows in df.items():
            print("# Kolonne: ", "\n")
            columnInsertSql = "INSERT INTO DataSets (Hour, BlockBuyNet, BlockSell, RejectedBlockBuy, RejectedBlockSell, NetImports) VALUES"
            rowCounter = 0

            for column in rows.items():
                columnInsertSql += str(column)

                if rowCounter != len(list(rows.items())):
                    columnInsertSql += ", "
                rowCounter += 1

            print("## SQL: " + columnInsertSql)

            cursor.execute(columnInsertSql)
            cursor.commit()

这是我打印df.dropna (axis = 1, how = 'all')时的结果：

小时0 1 ... 21 22 23

0已接受大宗购买112112 ... 227 52 52

1个已接受大宗卖出1573.2 1575.2 ... 1833.8 1728.3 1649.3

2个拒绝购买的商品NaN NaN ... NaN NaN NaN

3次否决销售NaN NaN ... NaN NaN NaN

4个净进口2652.3 2505.9 ... 2932 2962 2897

Answer 1

看起来您正在尝试删除NA，但是却忘记了放置“ inplace”标志，这就是为什么在打印数据帧时似乎没有任何缺少值的行，而原始Df保持不变的原因。

 for sheets in ark:
    df = excelFile.parse(sheets).head(5)
    df.dropna(axis=1, how='all', inplace=True)

或者，您可以像这样重新声明DF：

 for sheets in ark:
    df = excelFile.parse(sheets).head(5)
    df = df.dropna(axis=1, how='all')

此外，我建议使用Pandas to_sql功能使您的生活更加轻松。您可以一次上传整个DF，而不是一次上传：

from sqlalchemy import create_engine
engine = create_engine('postgresql://scott:tiger@localhost:5432/mydatabase')

#Fill in your code to loop through workbooks here

for sheets in ark:
    df = excelFile.parse(sheets).head(5)
    df = df.dropna(axis=1, how='all')
    df.columns =['Hour','BlockBuyNet','BlockSell','RejectedBlockBuy','RejectedBlockSell','NetImports']
    df.to_sql('DataSets', con = engine, if_exists='append', index = False)

为什么我的程序不将其插入数据库？

1 个答案: