我最终得到了这个函数，它对任何可能有同样问题的人都很有效：

def find_mismatch(df1, df2, key_list):
  
  def is_mismatch(col):
    values = (df1[col] != df2[col]) 
    return values | (df1[col].isNull() & df2[col].isNotNull()) | (df1[col].isNotNull() & df2[col].isNull())
  
  result = df1.join(df2, key_list, "outer")
  
  # Selecting original columns from both DataFrames
  select_columns = [result[i] for i in key_list]
  
  for col in df1.columns:
    if col not in key_list:
      select_columns.extend([
          df1[col].alias(col + '_df1'),
          df2[col].alias(col + '_df2'),
          is_mismatch(col).alias(col + '_mismatch')
      ])
  
  result = result.select(*select_columns)
  
  mismatched_cols = result.where(
      reduce(lambda acc, e: acc | e, [result[c + '_mismatch'] for c in df1.columns if c not in key_list], F.lit(False))
  )
  mismatch_count = mismatched_cols.count()
  return mismatch_count, mismatched_cols