I would like to write a backdoor into my app to access the DB directly so that I can, for example, delete unwanted rows created during development or modify values for testing.
It seems there should libraries out there for this but I cannot find any.
If these libraries don't exist, how do you get SQLiteOpenHelper (or whatever) to give the structure of a database (tables and rows)?
Thank you, good people.
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I have an Android app I wrote that uses a sqllite database,(the app is used for the reservation) now I want to write the same app for iPhone and I want to use the same database I used in Android app. My question is can I use the same database in IOS.
If yes, then how can be used and where I place the sqllite database (I mean what folder)? and the users must be online to see the update in the database ?
Can I use an sqlite database created for android in IOS?
Yes, an SQLite database is a a file (or potentially 3 files if using Write-Ahead logging). It's simply a matter of copying the file(s).
Typically (i.e. if not specifying otherwise) an SQLite database is stored in data/data/your_package/database/the_database_name
where your_package is as per the App and the_database_name is the file name (may or may not have an extension).
Note if the database uses Write-ahead logging then 2 other files may exist, these being the_database_name-wal and the_database_name-shm. If they exist and are not empty, they need to also be copied.
However,
and the users must be online to see the update in the database ?
Is a completely different matter though. SQLite is not suited to a client/server situation, as you would have to write all the code to provide this functionality. See Appropriate Uses For SQLite.
Firebase may be an option if you don't mind Google's policies reqgarding information privacy. Otherwise you are likely then looking at something like MySQL/MariaDB.
Since there are two ways by which we can store or copy the data from database. one is from sqlite file which we lay in assets folder and another by database which is created programmatically.
I have following questions regarding the sqlite database in android:
1.which performs faster while getting performing select query from database and why?
2.what are the advantages of each approach.
I found on internet but i could not get any proper information, the only thing that i come to know by Googling is copying data from assets is better for static data like list of country(that is obvious because you will not perform any bulk operation of inserting data programmatcially in android). Any help regarding this is appreciated . :)
It does not make a difference.
Your select query is performed on the final database, which would be identical whether you copied it from assets, or imported it programmatically. Your approach to its creation does not influence its behaviour.
As for advantages, that's entirely up to you. In some scenarios, having a base database in assets would give you better, and easier to read, control over versioning, as you could commit it easily with your repository, vs. having thousands of SQL statements in code.
On the flip side, updating a database that you copy from the assets folder with each version could be difficult, especially if you modify data within the app frequently. Instead of programmatically simply altering the schema or data on update, you would have to export any modifications, copy the new database, and then import all your modifications by performing some form of merge.
I'm developing a library that will be able to be used across multiple apps. It serves the exact same function in each, and one of the goals of the library is to be as easy and painless to use as possible. In that way, I was hoping to use a SQLite db to store some important information relevant to the library, but NOT to the host app. I searched around and couldn't find anything confirming or denying the ability for libraries to have their own databases. Does anyone know if it is possible?
Thanks a lot.
Well, that depends upon what you mean by "the ability for libraries to have their own databases".
There is nothing stopping an Android library project -- or even a plain Android-compiled JAR -- from using SQLiteDatabase, SQLiteOpenHelper, and kin. So, from a code standpoint, the library can have its own database. You will need a Context object from the host app, at least for use with SQLiteOpenHelper, though.
That is because, from a file standpoint, the library does not exist outside of its hosting app. Hence, the database file will be stored in the app's portion of internal storage by default. You will need to take some steps to try to minimize the odds of collisions on database file name (e.g., mangle your library's package name into the filename), so the host app does not attempt to accidentally work with your library's data. The Context is supplied to SQLiteOpenHelper mostly so that it can call methods like getDatabasePath() to figure out where to put the database file.
Also, bear in mind that the host app can access your database, just as it can access its own. Please make sure that you document the rules regarding this database (e.g., do not use it directly, but use the library's API instead).
I have a huge set of data that I want to insert into the sqlite database before the user is able to do anything inside my application. Right now I have all my data stored in CSV files, then I parse those files and use DatabaseUtils.InsertHelper to do a bulk insertion, but this is taking to long to complete.
I stumbled on this tutorial some time ago and I'm wondering: is it safe to distribute a pre-generated sqlite file? Can I run into problems due to different versions of SQLite on different devices?
I'm planning to support Android 2.1 and higher.
I suppose it depends on your definition of safe. It is certainly possible as long as the database conforms to the metadata table spec Android expects, which is what that tutorial you stumbled upon is showing you. You won't have to worry about version conflicts with SQLite as that is a package built into the core platform and isn't something OEMs add to or implement anything on top of.
However, if by safe you mean "protected" you would need to take special steps to ensure that your database is not externally readable if that is a concern. If you simply place the preconstructed DB into assets/ and copy it over, anyone who can properly deconstruct an APK file can view your database data. This may or may not be an issue for you.
The best approach is to populate this data in the database, keep the database in assets & then copy it to the device ... You can follow this complete sample code here.
I need to ship an app that uses read-only access to several preexisting SQLite3 DB's that each are a couple of 100MB's, total combines size > 1GB. The databases are created on a Mac, and are currently used in a shipping iOS app. I am pretty proficient in Java, but new to Android.
This leads to the following questions:
1) Will I need to modify the databases? I only plan to use them with SQLiteDatabase::rawQuery queries, so no nee for bindings and metadata I hope.
2) It it really correct that even if the DB's will only be used as read-only, I'll have to copy them out of the app bundle or download them to user directory on first start-up?
3) The queries can be slow. I want to run them in a thread and provide data via a callback. Is this done the way it's done in normal Java (Runnable/Thread), or will I have to use another method?
4) Is there anything else that's obvious to the Androidan that I have clearly missed?
1) No, it should work fine.
2) Yes, if you want to ship an APK that is over 50Mb you will need to use an expansion file.
3) For easy background tasks with a call back you could use an ASyncTask.
for a decent example of a sqlite helper class look here
you shouldnt need to edit the database. my sqlite databases work the same wether I access them via sqlite3 or with the android my sqlite helper class
once you copy them you can read and write
not really sure about this answer. i will say though that the database helper class above seems to work just fine (fast) but my db is smaller (500kb)
dont think so