Im trying to instance all database stored informations into a class in Dart, and use all the intances to manager an aplication based on instances, not in database select informations, because if i can instance only one time the database stored informations, i can do the process of manage information fast than im doing right now.

The question is how to do it, without every time i rerun a page it create another time all instances from database, for example, i insert a database select all itens and do a for in that elements and create a instance, but, every time i call the code, it will create again all intances of database, and it will return duplicate information to manager in app. How to create only one time (for example, after open the APP) and insert all rows in instance of a class?

Doing it, im not need to do SELECT in database everytime ill need some database information, and will open a conection with database only time, to do a single SELECT to get database informations, and next time when i open the conection, will to be insert/delete informations, saving resources and doing best perfomance.