mysql - Monitoring changes in SQL db using Java -


i want check changes in sql database not sure best approach be.

currently create object column (key, value) information , store arraylist. copy arraylist , make new 1 called "cache".

now, i'm doing: every x ms grabbing data sql db , comparing cached local copy. if there different e.g. value has been updated, inserted or deleted, have listener notify me.

is bad approach? should doing "select * table" query or there way can information want. want able see specific data has been modified e.g. row, column , value.

note: database generic.


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