Why is my SQLite Database not created/saved to disk? - android-emulator

I created code to create a SQLite database based on the article here.
The most pertinent code is:
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "Platypus.db";
private static final String TABLE_VENDORS = "vendors";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_VENDORID = "vendorId";
public static final String COLUMN_COMPANYNAME = "companyName";
public SQLiteHandlerVendors(Context context, String vendor,
SQLiteDatabase.CursorFactory factory, int company) {
super(context, DATABASE_NAME, factory, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
String CREATE_VENDORS_TABLE = "CREATE TABLE " +
TABLE_VENDORS + "("
+ COLUMN_ID + " INTEGER PRIMARY KEY," + COLUMN_VENDORID
+ " TEXT," + COLUMN_COMPANYNAME + " TEXT" + ")";
db.execSQL(CREATE_VENDORS_TABLE);
}
public void addVendor(Vendor vendor) {
ContentValues values = new ContentValues();
values.put(COLUMN_VENDORID, vendor.getVendorId());
values.put(COLUMN_COMPANYNAME, vendor.getCompanyName());
SQLiteDatabase db = this.getWritableDatabase();
db.insert(TABLE_VENDORS, null, values);
db.close();
}
Yet, although the insertions of data seem to be working -- the calls to addVendor() run without any exception being thrown with the following code:
protected void onPostExecute(String result) {
try {
JSONArray jsonArr = new JSONArray(result);
for (int i = 0; i < jsonArr.length(); i++) {
JSONObject jsonObj = jsonArr.getJSONObject(i);
String vendorId = jsonObj.getString("vendorId");
String companyName = jsonObj.getString("companyName");
Log.i("vendorId", vendorId);
Log.i("companyName", companyName);
// Prepare for writing to db
Vendor vend = new Vendor();
vend.setVendorId(vendorId);
vend.setCompanyName(companyName);
SQLiteHandlerVendors sqliteHandler = new SQLiteHandlerVendors(MainActivity.this, null, null, 1);
sqliteHandler.addVendor(vend);
}
} catch (JSONException j) {
System.out.println(j.getMessage());
Log.i("jsonEx", j.getMessage());
}
Log.i("GetVendorsTask.FromOnPostExecute", result);
}
I cannot locate the Platypus.db file that should have been created.
This article says, "If your application creates a database, this database is by default saved in the directory DATA/data/APP_NAME/databases/FILENAME."
A global search for "Platypus.DB" on my hard drive turns up nothing. Is the database created not being persisted, or is there some other reason why I'm not finding it?
I tried to find it by adding this code:
Log.i("Data Dir", Environment.getDataDirectory().toString());
...and when LogCat gives me is:
04-07 12:36:47.133 1089-1089/platypus.app I/Data Dirīš• /data
There is no "data" folder in C:\Users\clay\AndroidStudioProjects\Platypus, nor is there one in the root of my hard drive (*C:*).
Can the data dir/file only be viewed in some virtual space, in a file system for the emulator or so? If so, how can I actually access the emulator's file system to view this data?
UPDATE
Okay, I opened up this view, and navigated to data/data/hhs (the app's name is really "hhs" not "platypus"):
...but still do not see HHS.DB (I see no "databases" folder below all that)...
UPDATE 2
If I select the "<=" button ("Pull a file from the device") with the file with the size of 16384 highlighted, it does open the "Get Device File" dialog with a filename of "HHS.DB" (just what I was hoping to find).
But, why is its path "data\data\hhs\unnamed folder\unnamed file" instead of "data\data\hhs\databases\HHS.DB"?
The other file (size 8720) is HHS.db-journal
UPDATE 3
After saving those files to my hard drive and downloading SQLite Data Browser, I'm able to verify that the records actually were written to the table:
SQLite Data Browser is a great tool for just such a need!
UPDATE 4
I don't know what changed/how it changed, but it's now working as it should:

There is no "data" folder in
C:\Users\clay\AndroidStudioProjects\Platypus, nor is there one in the
root of my hard drive (C:).
Yes that is corect.
Can the data dir/file only be viewed in some virtual space, in a file
system for the emulator or so? If so, how can I actually access the
emulator's file system to view this data?
Using Eclipse you can pull the db from your emulator
Goto windows open perspective. Goto DDMS
Then goto file explorer-> data->data->see your package name-> databases->Platypus.DB"
/data/data/[packagename]/databases/
You select the db and there is a option to pull the db and then you can use a sqlite browser to view the data

Related

how to make sure locks are released with ef core and postgres?

I have a console program that moves Data between two different servers (DatabaseA and DatabaseB).
Database B is a Postgres-Server.
It calls a lot of stored procedures and other raw queries.
I use ExecuteSqlRaw a lot.
I also use NpsqlBulk.EfCore.
The program uses the same context instance for DatabaseB during the whole run it takes to finish.
Somehow i get locks on some of my tables on DatabaseB that never get released.
This happens always on my table mytable_fromdatabase_import.
The code run on that is the following:
protected override void AddIdsNew()
{
var toAdd = IdsNotInDatabaseB();
var newObjectsToAdd = GetByIds(toAdd).Select(Converter.ConvertAToB);
DatabaseBContext.Database.ExecuteSqlRaw("truncate mytable_fromdatabase_import; ");
var uploader = new NpgsqlBulkUploader(DatabaseBContext);
uploader.Insert(newObjectsToAdd); // inserts data into mytable_fromdatabase_import
DatabaseBContext.Database.ExecuteSqlRaw("call insert_myTable_from_importTable();");
}
After i run it the whole table is not accessable annymore and when i query the locks on the server i can see there is a process holding it.
How can i make sure this process always closes and releases its locks on tables?
I thought ef-core would do that automaticaly.
-----------Edit-----------
I just wanted to add that this is not a temporary problem during the run of the console. When i run this code and it is finished my table is still locked and nothing can access it. My understanding was that the ef-core context would release everything after it is disposed (if by error or by being finished)
The problem had nothing to do with ef core but with a wrong configured backupscript. The program is running now with no changes to it and it works fine
For concrete task you need right tools. Probably you have locks when retrieve Ids and also when trying to do not load already imported records. These steps are slow!
I would suggest to use linq2db (disclaimer, I'm co-author of this library)
Create two projects with models from different databases:
Source.Model.csproj - install linq2db.SQLServer
Destination.Model.csproj - install linq2db.PostgreSQL
Follow instructions in T4 templates how to generate model from two databases. It is easy and you can ask questions on linq2db`s github site.
I'll post helper class which I've used for transferring tables on my previous project. It additionally uses library CodeJam for mapping, but in your project, for sure, you can use Automapper.
public class DataImporter
{
private readonly DataConnection _source;
private readonly DataConnection _destination;
public DataImporter(DataConnection source, DataConnection destination)
{
_source = source;
_destination = destination;
}
private long ImportDataPrepared<TSource, TDest>(IOrderedQueryable<TSource> source, Expression<Func<TSource, TDest>> projection) where TDest : class
{
var destination = _destination.GetTable<TDest>();
var tableName = destination.TableName;
var sourceCount = source.Count();
if (sourceCount == 0)
return 0;
var currentCount = destination.Count();
if (currentCount > sourceCount)
throw new Exception($"'{tableName}' what happened here?.");
if (currentCount >= sourceCount)
return 0;
IQueryable<TSource> sourceQuery = source;
if (currentCount > 0)
sourceQuery = sourceQuery.Skip(currentCount);
var projected = sourceQuery.Select(projection);
var copied =
_destination.BulkCopy(
new BulkCopyOptions
{
BulkCopyType = BulkCopyType.MultipleRows,
RowsCopiedCallback = (obj) => RowsCopiedCallback(obj, currentCount, sourceCount, tableName)
}, projected);
return copied.RowsCopied;
}
private void RowsCopiedCallback(BulkCopyRowsCopied obj, int currentRows, int totalRows, string tableName)
{
var percent = (currentRows + obj.RowsCopied) / (double)totalRows * 100;
Console.WriteLine($"Copied {percent:N2}% \tto {tableName}");
}
public class ImporterHelper<TSource>
{
private readonly DataImporter _improrter;
private readonly IOrderedQueryable<TSource> _sourceQuery;
public ImporterHelper(DataImporter improrter, IOrderedQueryable<TSource> sourceQuery)
{
_improrter = improrter;
_sourceQuery = sourceQuery;
}
public long To<TDest>() where TDest : class
{
var mapperBuilder = new MapperBuilder<TSource, TDest>();
return _improrter.ImportDataPrepared(_sourceQuery, mapperBuilder.GetMapper().GetMapperExpressionEx());
}
public long To<TDest>(Expression<Func<TSource, TDest>> projection) where TDest : class
{
return _improrter.ImportDataPrepared(_sourceQuery, projection);
}
}
public ImporterHelper<TSource> ImprortData<TSource>(IOrderedQueryable<TSource> source)
{
return new ImporterHelper<TSource>(this, source);
}
}
So begin transferring. Note that I have used OrderBy/ThenBy to specify Id order to do not import already transferred records - important order fields should be Unique Key combination. So this sample is reentrant and can be re-run again when connection is lost.
var sourceBuilder = new LinqToDbConnectionOptionsBuilder();
sourceBuilder.UseSqlServer(SourceConnectionString);
var destinationBuilder = new LinqToDbConnectionOptionsBuilder();
destinationBuilder.UsePostgreSQL(DestinationConnectionString);
using (var source = new DataConnection(sourceBuilder.Build()))
using (var destination = new DataConnection(destinationBuilder.Build()))
{
var dataImporter = new DataImporter(source, destination);
dataImporter.ImprortData(source.GetTable<Source.Model.FirstTable>()
.OrderBy(e => e.Id1)
.ThenBy(e => e.Id2))
.To<Dest.Model.FirstTable>();
dataImporter.ImprortData(source.GetTable<Source.Model.SecondTable>().OrderBy(e => e.Id))
.To<Dest.Model.SecondTable>();
}
For sure boring part with OrderBy can be generated automatically, but this will explode this already not a short answer.
Also play with BulkCopyOptions. Native Npgsql COPY may fail and Multi-Line variant should be used.

How-to get the code for downloading metadata along with images in IBM content manager

I am trying to find the code in java API which works with cm IBM.. the sample code is there but it is just for logging in.. can anyone help to get the code to download the images along with metadata
as you said you have basic connection code, use the below function to download the document..
public String retrieveDocument(CMBConnection connection, CMBItem item)
throws CMBException, IOException, Exception
{
// Get an instance of data management bean
CMBDataManagement dataManagement = connection.getDataManagement();
// Set the current data item
dataManagement.setDataObject(item);
// Retrieve the original file name
CMBObject object = dataManagement.getContent(0);
String inputFileName = object.getOriginalFileName();
// Parse the file name from the full path
int pos=inputFileName.lastIndexOf("\\");
inputFileName = inputFileName.substring(pos+1);
// Write the document content to a new file
String fileName = System.getProperty("user.dir")
+ File.separator + inputFileName;
System.out.println("Output file name " + fileName);
FileOutputStream fileoutstream = new FileOutputStream(fileName);
fileoutstream.write(dataManagement.getContent(0).getData());
fileoutstream.close();
// Return file name
return fileName;
}

cursor count is 1 whereas the table has 3 rows

I m trying to populate sql table and then retrieve data from it. Following is my code.
public void addQuestion(Question quest)
{
int id = 1;
ContentValues values = new ContentValues();
SQLiteDatabase db = this.getWritableDatabase();
db.execSQL("DROP TABLE IF EXISTS " + TABLE_QUEST1);
onCreate(db);
values.put(KEY_QUES, quest.getQuestion());
values.put(KEY_ANSWER, quest.getAnswer());
values.put(KEY_OPTA, quest.getOptA());
values.put(KEY_OPTB, quest.getOptB());
values.put(KEY_OPTC, quest.getOptC());
db.insert(TABLE_QUEST1, null, values);
System.out.println("Added in database: " + quest.getQuestion());
}
public ArrayList<Question> getAllQuestions() {
System.out.println("getting rows 1");
ArrayList<Question> quesList = new ArrayList<Question>();
System.out.println("getting rows 2");
Cursor cursor = null;
SQLiteDatabase db = getReadableDatabase();
System.out.println("getting rows ");
cursor = db.rawQuery("SELECT * FROM " + TABLE_QUEST1, null);
if (!cursor.moveToFirst()) {
System.out.println("No data in the database ");
} else {
System.out.println("theres data in the database ");
quesList = new ArrayList<Question>();
do {
System.out.print("total rows " + cursor.getCount());
Question quest = new Question();
quest.setID(cursor.getInt(0));
quest.setQuestion(cursor.getString(1));
quest.setAnswer(cursor.getString(2));
quest.setOptA(cursor.getString(3));
quest.setOptB(cursor.getString(4));
quest.setOptC(cursor.getString(5));
quesList.add(quest);
} while (cursor.moveToNext());
cursor.close();
}
}
I have 4 rows of data in my table and I can see that with the print statement "added in database"
but when i actually read it the cursor just reads row 1 and moves out of the while loop. what could potentially be wrong.
tia
Your code was absolutely fine except placing drop command in the loop. As mentioned in the earlier comments, please make sure to avoid calling drop query each time and you'll find the result.
As Santosh has pointed out DROPPING the table (as per db.execSQL("DROP TABLE IF EXISTS " + TABLE_QUEST1);) and then re-creating it (as per onCreate(db);) will delete the table and then re-create the table removing any rows/data that had previously been added to the table.
As such it's simply a matter of removing those two lines of code, Also there appears to be no need for the line int id = 1;, so perhaps remove this, as per :-
public void addQuestion(Question quest)
{
ContentValues values = new ContentValues();
SQLiteDatabase db = this.getWritableDatabase();
values.put(KEY_QUES, quest.getQuestion());
values.put(KEY_ANSWER, quest.getAnswer());
values.put(KEY_OPTA, quest.getOptA());
values.put(KEY_OPTB, quest.getOptB());
values.put(KEY_OPTC, quest.getOptC());
db.insert(TABLE_QUEST1, null, values);
System.out.println("Added in database: " + quest.getQuestion());
}
P.S. you may consider not using hard coded column offsets but instead obtain offsets according to column names by utilising the getColumnIndex(column_name) Cursor method. e.g. :-
Question quest = new Question();
quest.setID(cursor.getInt(cursor.getColumnIndex("name_of_your_id_columm")));
quest.setQuestion(cursor.getString(cursor.getColumnIndex(KEY_QUES)));
quest.setAnswer(cursor.getString(cursor.getColumnIndex(KEY_ANSWER)));
quest.setOptA(cursor.getString(cursor.getColumnIndex(KEY_OPTA)));
quest.setOptB(cursor.getString(cursor.getColumnIndex(KEY_OPTB)));
quest.setOptC(cursor.getString(cursor.getColumnIndex(KEY_OPTC)));
quesList.add(quest);
Noting that instead of "name_of_your_id_columm", you may have something like KEY_ID defined, if so use that, thus you have a single definition so it reduces the chance of inadvertently mispelling column names or miscalculating the offsets.

Using Drag-Sort ListView with SQLite DB

I'm trying to create a simple to-do-list app with an SQLite DB and a Drag-Sort ListView.
Right now I am binding data from an SQLite database cursor into a ListView using a SimpleCursorAdapter and adding items with an EditText view as explained in this tutorial.
I have moved everything into one activity and I have swapped the plain ListView with a Drag-Sort ListView. My issue is connecting the DB and Drag-Sort ListView together. The DLSV demos use a predefined array to fill fill the DSLV.
Snippet form DSLV:
DragSortListView lv = (DragSortListView) getListView();
lv.setDropListener(onDrop);
lv.setRemoveListener(onRemove);
array = getResources().getStringArray(R.array.jazz_artist_names);
list = new ArrayList<String>(Arrays.asList(array));
adapter = new ArrayAdapter<String>(this, R.layout.list_item1, R.id.text1, list);
setListAdapter(adapter);
Snippet from my existing code:
mDbHelper = new NotesDbAdapter(this);
mDbHelper.open();
...
mDbHelper.createNote(noteName, "");
fillData();
private void fillData() {
// Get all of the notes from the database and create the item list
Cursor c = mDbHelper.fetchAllNotes();
startManagingCursor(c);
String[] from = new String[] { NotesDbAdapter.KEY_TITLE };
int[] to = new int[] { R.id.text1 };
// Now create an array adapter and set it to display using our row
SimpleCursorAdapter notes =
new SimpleCursorAdapter(this, R.layout.notes_row, c, from, to);
setListAdapter(notes);
}
Thank you and sorry if this doesn't make all that much sense.
Since you cannot reorder the items in a Cursor, you have to create a mapping between Cursor positions and ListView positions. This is done for you by the DragSortCursorAdapter class and subclasses so that the drag and drop reordering is maintained visually. If you need the new orders persisted (like to your database), then you must implement that logic yourself. The method getCursorPositions() will help you with this.
I have made use of Drag sort list view. Its amazing! but instead of using the dragsortcursoradapter i created my own trick. here it is.
What i have done is that whenever i swapped any item, i passed the new swapped list in an array to the database, deleted the table and recreated the new updated table. here is my code
here is the code snippet from my database handler
public void onUpdateToDoTable(ArrayList<Task> taskList) {
SQLiteDatabase db = this.getWritableDatabase();
db.execSQL("DROP TABLE IF EXISTS " + TABLE_TASKTODO);
String CREATE_TASK_TODO_TABLE = "CREATE TABLE IF NOT EXISTS "
+ TABLE_TASKTODO + "(" + SEQ_ID + " INTEGER PRIMARY KEY,"
+ TASK_NAME + " TEXT )";
db.execSQL(CREATE_TASK_TODO_TABLE);
for (int i = 0; i < taskList.size(); i++) {
ContentValues values = new ContentValues();
values.put(TASK_NAME, taskList.get(i).getTask());
db.insert(TABLE_TASKTODO, null, values);
}
db.close();
}
then on using drop listener
i called the above method..
private DragSortListView.DropListener onDrop = new DragSortListView.DropListener() {
#Override
public void drop(int from, int to) {
Task item = adapter.getItem(from);
adapter.notifyDataSetChanged();
adapter.remove(item);
adapter.insert(item, to);
db.onUpdateToDoTable(list);
Log.d("LIST", db.getAllToDoTasks().toString());
}
};
db is my object of database handler. whole source code is available at dragdroplistview. amazing example. this was a life saver for me. Ciao!
There is a github project available at https://github.com/jmmcreynolds/dslv-db-demo
This demo includes a working example of how to setup a DragSortListView that will save the changes that you make to the list (position, add/delete) to a database.
I have used it just now. Its perfect demo project available for using DSLV with SQLiteDB.
Thanks to github user jmmcreynolds.

Crystal report xi + c#.net document load problem

I have a crystal report which gives me undefined error when opening document, does any one come across this type of error, below is the coding:
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
///create instance of class first
ReportDocument rpDoc = new ReportDocument();
///load the report
rpDoc.Load(#"TicketingBasic.rpt");////------->>>problem is here
///pass the report to method for dataInfo
getDBInfo(rpDoc);
/// et the source for report to be displayed
CrystalReportViewer1.ReportSource = rpDoc;
}
protected static void getDBInfo(ReportDocument rpDoc)
{
///Connection Onject
ConnectionInfo cn = new ConnectionInfo();
///DataBase,Table, and Table Logon Info
Database db;
Tables tbl;
TableLogOnInfo tblLOI;
///Connection Declaration
cn.ServerName = "???????????";
cn.DatabaseName = "??????????";
cn.UserID = "?????????";
cn.Password = "????????????";
//table info getting from report
db = rpDoc.Database;
tbl = db.Tables;
///for loop for all tables to be applied the connection info to
foreach (Table table in tbl)
{
tblLOI = table.LogOnInfo;
tblLOI.ConnectionInfo = cn;
table.ApplyLogOnInfo(tblLOI);
table.Location = "DBO." + table.Location.Substring(table.Location.LastIndexOf(".") + 1);
}
db.Dispose();
tbl.Dispose();
}
}
Final code snippet is:
rpDoc.Load(Server.MapPath(#"TicketingBasic.rpt"));
Thank you all for the help.
The problem I am having now is report not printing or exporting to other types like .pdf,.xsl, .doc etc, any clue
so the error is literally "undefined error"? never seen that one before.
First guess is that you need the full physical path to the report.
rpDoc.Load(Server.MapPath(#"TicketingBasic.rpt"));
HttpServerUtility.MapPath
How are you handling the report outout?
When we do reports we set the file name:
ReportSource.Report.FileName = FileName;
Where filename is a string that is the name of the file (obviously). Then we select the report tables and export in whatever format. Try this.