RaqForum 41 No.
163 View  • 
     ...

Merge multiple files, remove duplicates and sort the result

 

There are multiple csv files having the same structure in a directory:

file-januar.csv

ID,From,To

1234,2022-01-01,2022-01-02

1235,2022-07-01,2022-08-20

file-februar.csv

ID,From,To

1234,2022-01-01,2022-01-02

1235,2022-08-21,2022-08-30

Use Java to do this: Combine these files, remove duplicate rows and sort rows by From, and save the result as a new file:

ID,From,To

1234,2022-01-01,2022-01-02

1235,2022-07-01,2022-08-20

1235,2022-08-21,2022-08-30

Write the following SPL code:

=T(\"d:\\result.csv\":directory@p(\"d:\\file-*.csv\").(T(~)).merge@u().sort(From))

T() function parses a file or writes data of a file to a new file. directory@p searches for target files according to the wildcard characters and returns files with full paths. merge@u merges records by rows or fileds; @u option finds the union. The symbol ~ represents the current varialbe in a loop.


Read How to Call a SPL Script in Java to find how to integrate SPL into a Java application.
Source:https://stackoverflow.com/questions/71508457/java-datastructure-like-a-table-without-using-a-database

 
 •  163 View  •