在iOS中处理超大型数据库

Question

I want to know how to handle very large DBs in iOS?

Explanation:

I am making an app for the company, it will be holding all daily transactions and operations (this means few hundreds to a couple thousands a day ). The app in fact just displays the daily transactions, but keeps everything in the DB just in case (so I can not delete them).

As there is a need for the app to be highly reactive, I am searching for a way to efficiently load (Core Data Fetch) just the latest operations, without being slowed down in the long run when the DB gets really large. Knowing that whenever an operation is updated, I refresh the displayed table immediately.

I can't find any article dealing with this on iOS, so I can't find any good practice or a correct way to handle it.

On a MySQL server, I'd do like this: * Set up a DB for daily "active" operations, when done, delete them and move them to a "finished" operations DB. * Set up a Cron job to dump/backup daily/monthly DBs by night, and having a fresh lightweight one for the next day.

Sadly, it doesn't seem possible to create a dynamic table on iOS, and even creating a "finished" DB, this will still require accessing a heavy DB at each closed operation, which can lead to a low memory crash.

Answer 1

actually I think you can try sqlite api to match the same operations in your MySQL server. However, you will have to drop the CoreData and rewrite everything instead, ie, TableView, TableCell, etc. to deal with the DataSource like this:

sqlite3 * tradeDB;
sqlite3_open_v2([path UTF8String], &tradeDB, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, nil);
sqlite3_stmt * recordset;
int res = sqlite3_prepare_v2(tradeDB, "select count(*) from someTable", -1, &recordset, nil);
if (res!=SQLITE_OK) {
    return nil;
}//end if

res = sqlite3_step(recordset);
if (res!=SQLITE_ROW) {
    _result = nil;
}else{
    char * res_char = (char*)sqlite3_column_text(recordset, 0);
    if (!res_char)
        _result = nil;
    else
        _result = [NSString stringWithUTF8String:res_char];
    //end if
}//end if
sqlite3_finalize(recordset);

if (!_result) {
    _result = @"0";
}//end if
return self;