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I need to intersect the dataframe columns with the database columns (defined in a list) before I execute a query. My current code looks like this:

db_columns_list = ['col1', 'col2', 'col3']
dataframe = dataframe[dataframe.columns & db_columns_list]
This works well, but I am getting the warning:
*FutureWarning: Index.__and__ operating as a set operation is deprecated, in the future this will be a logical operation matching Series.__and__.  Use index.intersection(other) instead
  dataframe = dataframe[dataframe.columns & db_columns_list]*
So I would like to convert it into something like:
dataframe = dataframe[dataframe.columns.intersection(db_columns_list)]
but with that I get the error:
*Unresolved attribute reference 'intersection' for class 'Iterator'* 
Please note that the database may contain more columns than the dataframe.
Therefore I believe the intersection is the correct way to approach this.
Thank you
intersection function can be applied as below.
Toy example,
db_columns_list = ['col1', 'col2', 'col3']
df=DataFrame({
    'col1':[1,2],
    'col3':[3,4]
## Solution
df[set(df.columns).intersection(set(db_columns_list))]
# Improved version with the help of `Mustafa Aydın` 
df[df.columns.intersection(db_columns_list)]
Output
    col3    col1
0   3       1
1   4       2
                pd.Index has an intersection method and works without casting to set. Your example works without both sets. I think the issue is different
– Mustafa Aydın
                May 9, 2021 at 7:23
                pd.Index has all the functionality of the set plus more for example - It's ordered and it can contain duplicates as well. So, I guess the problem is diff. here as suggested by @MustafaAydın
– Nk03
                May 9, 2021 at 7:27
                The new solution proposed: df[df.columns.intersection(db_columns_list)]   for me does not work. I get: Unresolved attribute reference 'intersection' for class 'Iterator'.  The previous one with set worked.
– Forna
                May 9, 2021 at 7:28
                nw, Thanks for +1, We are here to help each other. It's okay if someone  downvotes(his choice).
– Utsav
                May 9, 2021 at 7:46
Hope the below code will fix your issue.Intersection works only for sets
common_cols = list(set(dataframe.columns).intersection(set(db_columns_list)))
dataframe = dataframe[common_cols]
        
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