python - 使用python从BytesIO创建一个excel文件

Question

我正在使用 pandas将 excel 存储到的库 bytesIO内存。后来，我把这个bytesIO存起来对象到 SQL Server 如下 -

    df = pandas.DataFrame(data1, columns=['col1', 'col2', 'col3'])
    output = BytesIO()
    writer = pandas.ExcelWriter(output,engine='xlsxwriter')
    df.to_excel(writer)
    writer.save()
    output.seek(0)
    workbook = output.read()

    #store into table
    Query = '''
            INSERT INTO [TABLE]([file]) VALUES(?)
            '''
    values = (workbook)
    cursor = conn.cursor()
    cursor.execute(Query, values)
    cursor.close()
    conn.commit()

   #Create excel file.
   Query1 = "select [file] from [TABLE] where [id] = 1"
   result = conn.cursor().execute(Query1).fetchall()
   print(result[0])

现在，我想从表中拉回 BytesIO 对象并创建一个 excel 文件并将其存储在本地。我该怎么做？

Answer 1

最后，我得到了解决方案。以下是执行的步骤:

获取 Dataframe 并将其转换为 excel 并以 BytesIO 格式存储在内存中。

将 BytesIO 对象存储在具有 varbinary(max)

的数据库列中

拉取存储的 BytesIO 对象并在本地创建一个 excel 文件。

python 代码:

#Get Required data in DataFrame:
df = pandas.DataFrame(data1, columns=['col1', 'col2', 'col3'])

#Convert the data frame to Excel and store it in BytesIO object `workbook`:
output = BytesIO()
writer = pandas.ExcelWriter(output,engine='xlsxwriter')
df.to_excel(writer)
writer.save()
output.seek(0)
workbook = output.read()

#store into Database table
Query = '''
        INSERT INTO [TABLE]([file]) VALUES(?)
        '''
values = (workbook)
cursor = conn.cursor()
cursor.execute(Query, values)
cursor.close()
conn.commit()

#Retrieve the BytesIO object from Database
Query1 = "select [file] from [TABLE] where [id] = 1"
result = conn.cursor().execute(Query1).fetchall()

WriteObj = BytesIO()
WriteObj.write(result[0][0])  
WriteObj.seek(0)  
df = pandas.read_excel(WriteObj)
df.to_excel("outputFile.xlsx")