A file has multiple columns of data. The first row is the column name, and the second row is the data record. Compare the key columns in the file, delete the duplicate rows in the key column or keep only the duplicate rows.
The current sales order table order_2018.xlsx for 2018, some of the data are as follows:
There are multiple Excel files Book1.xlsx, Book2.xlsx, Book3.xlsx,…, the naming rule of these files is Book[N].xlsx, N is a number starting from 1, the data in the file is as follows: