There is no functionality for compressing backup (.sql) files in the sja-code itself. However as the SJA is a command-line tool it can be launched from a batch (.bat on Windows) -file or from within a script/an application. And any 'ZIPPER' (or whatever compressing algorithm you prefer) -program that can be executed from command line may be called from the same batch file or program. Refer to the documentation of your preferred zip/compression program for the syntax to use.

This is a 'skeleton' of sample .bat file that uses the freeware Filzip (www.filzip.com) program. SJA does the backup. FILZIP adds all *.sql files in the specified folder to the 'backups.zip' archive and the Windows' delete command next deletes the .sql -files as they are not needed any more.

<path to>sja.exe my_backupjob.xml

<path to>filzip.exe -a -rp <path to>backups.zip *.sql

delete <path to >*.sql.

Note that with this example it probably would be practical if you used the option to add a timestamp to .sql file name in the SJA job definition file. Also this .bat file can be scheduled from the Windows Scheduler (or any other functional scheduler)