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Android - How to Use SQLiteDatabase.open?

i'm trying to use

SQLiteDatabase.openDatabase(
    "/data/data/edwin11.myapp/databases/myapp.db", null, (SQLiteDatabase.CREATE_IF_NECESSARY | SQLiteDatabase.NO_LOCALIZED_COLLATORS));

to create/open a database instead of making use of the SQLiteOpenHelper (because i want to pass in the flag SQLiteDatabase.NO_LOCALIZED_COLLATORS.

However, i am getting this exception for that line of code:

04-18 09:50:03.585: ERROR/Database(3471): sqlite3_open_v2("/data/data/edwin11.myapp/databases/myapp.db", &handle, 6, NULL) failed
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): java.lang.RuntimeException: An error occured while executing doInBackground()
04-18 09:50:03.665: ERROR/AndroidRuntime(3471):     at android.os.AsyncTask$3.done(AsyncTask.java:200)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471):     at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:234)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471):     at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:258)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471):     at java.util.concurrent.FutureTask.run(FutureTask.java:122)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471):     at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:648)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471):     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:673)
04-18 09:50:03.665: ERROR/AndroidRunt开发者_如何学Goime(3471):     at java.lang.Thread.run(Thread.java:1060)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): Caused by: android.database.sqlite.SQLiteException: unable to open database file
04-18 09:50:03.665: ERROR/AndroidRuntime(3471):     at android.database.sqlite.SQLiteDatabase.dbopen(Native Method)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471):     at android.database.sqlite.SQLiteDatabase.<init>(SQLiteDatabase.java:1584)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471):     at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:638)
...

Doing some testing just before that line of code (using File.isExists) shows that the file /data/data/edwin11.myapp/databases/myapp.db does not exist.

Would that be the cause of the error? (Or am i just using SQLiteDatabase.openDatabase the wrong way?)

Would it help if i create the file beforehand? (Shouldn't that be taken care of by the SQLiteDatabase.CREATE_IF_NECESSARY flag that i passed in?)

If creating the file manually is the way to go, is it just an empty file, or do i have to write something to it?

Thanks and Regards.


Database files exist in the following path structure:

   String sDbPath = "/data/data/" + YourMainActivityClass.class.getPackage().getName() + "/databases/YourDBFileName";

E.g.: If your application exists in a package named; com.foo.bar, and the main Activity class name is BabarActivity, with DB file name MyData.db you can issue the above command as;

String sDbPath = "/data/data/" + com.foo.bar.BabarActivity.class.getPackage().getName() + "/databases/MyData.db";

Now, you can check whether the database file exists using this method:

boolean isDbExist() {
    SQLiteDatabase checkDB = null;

    try {
        checkDB = SQLiteDatabase.openDatabase(sDbPath, null,
                SQLiteDatabase.OPEN_READONLY);
    } catch (SQLiteException e) {
        Log.d(DB_NAME, "Database does't exist yet.", e);
    }

    if (checkDB != null) {
        checkDB.close();
        checkDB = null;
        return true;
    } else 
        return false;
}

Hope this helps!

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