How to specify database connection using statement method in Laravel
I am running a raw query on Laravel using DB::statement() method. This statement needs to fetch data from my secondary database.
I wonder if there is any clean way to specify database connection t...
I am new in Django and having a hard time figuring out how to print what an object have inside. I mean type and value of the variable with its members inside. Just like Laravel's dd(object) function.
文章浏览阅读2.3w次,点赞16次,收藏40次。问题描述有没有办法检查一个Pandas DataFrame中是否存在一列?假设我有以下DataFrame: import pandas as pd from random import randint df = pd.DataFrame({'A': [randint(1, 9) for x in xrange(10)], 'B': [randint(1, 9)*10 for_pandas判断是否存在某列