连接后如何在 Pyspark 数据框中选择和排序多列 [英] How to select and order multiple columns in a Pyspark Dataframe after a join

问题描述

我想从现有数据帧(在连接后创建)中选择多个列，并希望将这些字段排序为我的目标表结构.怎么做到呢 ?我使用的方法如下.在这里，我可以选择所需的必要列，但无法按顺序制作.

I want to select multiple columns from existing dataframe (which is created after joins) and would like to order the fileds as my target table structure. How can it be done ? The approached I have used is below. Here I am able to select the necessary columns required but not able to make in sequence.

Required (Target Table structure) :
hist_columns = ("acct_nbr","account_sk_id", "zip_code","primary_state", "eff_start_date" ,"eff_end_date","eff_flag")

account_sk_df = hist_process_df.join(broadcast(df_sk_lkp) ,'acct_nbr','inner' )
account_sk_df_ld = account_sk_df.select([c for c in account_sk_df.columns if c in hist_columns])

>>> account_sk_df
DataFrame[acct_nbr: string, primary_state: string, zip_code: string, eff_start_date: string, eff_end_date: string, eff_flag: string, hash_sk_id: string, account_sk_id: int]


>>> account_sk_df_ld
DataFrame[acct_nbr: string, primary_state: string, zip_code: string, eff_start_date: string, eff_end_date: string, eff_flag: string, account_sk_id: int]

account_sk_id 需要排在第二位.这样做的最佳方法是什么?

The account_sk_id need to be in 2nd place. What's the best way to do this ?

推荐答案

尝试仅通过提供列表来选择列，而不是通过迭代现有列并且排序应该没问题:

Try selecting columns by just giving a list, not by iterating existing columns and ordering should be OK:

account_sk_df_ld = account_sk_df.select(*hist_columns)

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