I have fourteen opencart databases hosted in different servers and I have a central database in a different server which stores only specific/needed details from every site and its mainly used for studying the trend and for order processing . In each 10 minutes( Anytime below this time is making the server go down ) I am collecting data from different db and storing in different fotmat( tables are different ) using cron job. Because of this I have delay around 30 minutes and I am in a situation where I need to sync the data almost like real-time( refresh in each 50 secs ).
I am looking for a solution which will help me to sync data in central db whenever the data in different db are changed. I can not afford to go for a paid service like percona for now.