[SOLVED]What would be the best way to have database support in my application.

ealione

Hi SGaist, thanks for the comment, as per usual it's right to the point.
I will implement it this way.

Leonardo

You don't need to create your database programmatically. You could create an empty database with all your tables and relationships and store it as a resource in your app. Then you would copy this resource to a writable location if it didn't exist yet. That's what I suggested. It would be like a template database.

ealione

Indeed, it should be faster too.

ealione

The location created from this command

    db_path = QDir(QStandardPaths::writableLocation(QStandardPaths::AppDataLocation)).filePath("database.db");

does not seem to actually exist in my system, moreover the copy command fails.

Is it normal that db_path returns a location that does not exist?

SGaist

What value are you getting ?

ealione

db_path has a value of "C:/Users/eali/AppData/Roaming/ealione/v002/database.db"

SGaist

Looks good

What is your problem with it ?

rturrentine

Maybe you think the folder doesn't exist because the "AppData" folder is hidden by default.

ealione

Looks correct indeed, the thing is that it does not exist (not simply hidden), and the copy command:

QFile::copy(":assets/database/database.db", db_path returns false.

rturrentine

Is ":assets" Android specific? Also should it be "assets:/datatbase...."

Leonardo

QStandardPaths returns a writable path for you. It doesn't guarantee you that it exists. If if doesn't, create it using QDir.mkpath()

http://doc.qt.io/qt-5/qdir.html#mkpath

As you know it's a writable location, it won't be a problem.

=========

@rturrentine is right also. ":assets" is for android. For Qt resources, you should use ":/database/database.db".

rturrentine

BTW, here is a link to a related post:

http://forum.qt.io/topic/29289/solved-qt5-1-android-how-to-bundle-and-use-sqlite-database-in-application