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Android cannot insert into SQLite3 DB

I am trying to insert some data into and SQLite DB on android, but the code below just does not work. Can anyone spot the issue.
db = this.openOrCreateDatabase("data_7.db", 0, null);
db.execSQL("CREATE TABLE IF NOT EXISTS 'group' (my_id TEXT NOT NULL, my_key TEXT NOT NULL)");
db.execSQL("INSERT INTO 'group' (my_id, my_key) VALUES ('abc', '123')");
db.close();
After running the code I extracted the SQLite file off the emulator and opened it using an SQLite GUI viewer, the table was created but no data was inserted.
Note:
I have searched through this site all day and could not find a
suitable answer to this issue
I would like to do this without the aid of helper methods like
.insert(). ie. I need to user pure SQL

Try out this way:
"INSERT INTO group (my_id, my_key) " + "VALUES ('" + field_one + "', '" + field_two + "')";

you have to create the table in the method onCreate() that is found on the Dababase class that you have to build like this:
public class Database extends SQLiteOpenHelper
{
public static final String DB_NAME="YourDBName";
public static final int VERSION=1;
Context context=null;
public Database(Context context)
{
super(context, DB_NAME, null, VERSION);
this.context=context;
}
#Override
public void onCreate(SQLiteDatabase db)
{
try
{
String sql="CREATE TABLE group(my_id TEXT NOT NULL PRIMARY KEY, my_key TEXT NOT NULL)";
String insert="INSERT INTO group VALUES('abc','123');";
db.execSQL(sql);
db.execSQL(insert);
}
catch(Exception e)
{
Log.d("Exception", e.toString());
}
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
db.execSQL("DROP TABLE IF EXISTS group");
onCreate(db);
}
}
Make sure that the old database is deleted or change the version to 2 in order to execute the query.
If you need to execute this query you need to write:
Database db=new Database();
SQLiteDatabasse read=db.getReadableDatabase();

Android SQLite Upgrade without losing data

I have created a SQLite database successfully and it works fine. However when the onUpgrade method is called, I'd like to do so without losing data. The app I'm developing is a quiz app. Simply, when the onCreate method is called I create and prepopulate a database with questions, answers etc. The last column is whether they have set the question as a favourite or not. What I would like to do is that when the onUpgrade method is called, I'd like to temporarily save that one column, drop the whole database, recreate it with any edits I've made to old questions and add any new questions then re-add back the questions that they set as favourites.
So one option I tried was the following:
db.execSQL("ALTER TABLE quiz RENAME TO temp_quiz");
onCreate(db);
db.execSQL("INSERT INTO quiz (favouries) SELECT favourites FROM temp_quiz");
db.execSQL("DROP TABLE IF EXISTS temp_quiz");
However this doesn't work owing to the fact INSERT INTO just adds new rows rather than replacing the existing rows. I have also tried REPLACE INTO, INSERT OR REPLACE INTO and
db.execSQL("INSERT INTO quiz (_id, favouries) SELECT _id, favourites FROM temp_quiz");
of which none work.
Currently I do have it set up to work by altering the name of the table, calling the onCreate(db) method and then setting up a cursor which reads each row and uses the db.update() method as shown below:
int place = 1;
int TOTAL_NUMBER_OF_ROWS = 500;
while (place < TOTAL_NUMBER_OF_ROWS) {
String[] columns = new String[] { "_id", ..........., "FAVOURITES" };
// not included all the middle columns
Cursor c = db.query("temp_quiz", columns, "_id=" + place, null, null, null, null);
c.moveToFirst();
String s = c.getString(10);
// gets the value from the FAVOURITES column
ContentValues values = new ContentValues();
values.put(KEY_FLAG, s);
String where = KEY_ROWID + "=" + place;
db.update(DATABASE_TABLE, values, where, null);
place++;
c.close();
}
However whilst this works it is extremely slow and will only get worse as my number of questions increases. Is there a quick way to do all this?
Thank you! P.S. Ideally it should only update the row if the row is present. So if in an upgrade I decide to remove a question, it should take this into account and not add a new row if the row doesn't contain any other data. It might be easier to get it to remove rows that don't have question data rather than prevent them being added.

changed it to:
db.execSQL("UPDATE new_quiz SET favourites = ( SELECT old_quiz.favourites
FROM old_quiz WHERE new_quiz._id = old_quiz._id) WHERE EXISTS
( SELECT old_quiz.favourites FROM old_quiz WHERE new_quiz._id = old_quiz._id)");
Which works :D

public class DataHelper extends SQLiteOpenHelper {
private static final String dbName="dbName";
private Context context;
private SQLiteDatabase db;
private final static int version = 1;
public static final String SurveyTbl = "CREATE TABLE SurveyTbl (SurveyId TEXT PRIMARY KEY, Idref TEXT, SurveyDate TEXT)";
public DataHelper(Context context) {
super(context, dbName, null, version);
this.db = getWritableDatabase();
this.context = context;
Log.i("", "********************DatabaseHelper(Context context)");
}
#Override
public void onCreate(SQLiteDatabase db) {
try {
db.execSQL(SurveyTbl);
} catch (Exception e) {
Log.i("", "*******************onCreate");
}
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
try {
db.execSQL("ALTER TABLE HandpumpSurveyTbl ADD COLUMN NalYozna TEXT");
} catch (Exception e) {
Log.i("", ""+e);
}
onCreate(db);
}
}

I didn't get to see your Quiz table schema, but I assume it has fields like "question", "answer", "favorites", and some kind of a unique primary key to identify each question, which I will just call rowId for now.
// after renaming the old table and adding the new table
db.execSQL("UPDATE new_quiz SET new_quiz.favorites = old_quiz.favorites where new_quiz.rowId = old_quiz.rowId");
That will update only the rows of the new quiz table that match the old quiz table, and set the favorites value from the old quiz table.
I assume you have some kind of a unique identifier to identify each question, so instead of the rowId above, you'll use that (question number or something).

For who don't know yet how to upgrade the version of the SQLite when upgrading the database schema for example, use the method needUpgrade(int newVersion)!
My code:
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){
if(newVersion>oldVersion){
db.execSQL(scriptUpdate);
db.needUpgrade(newVersion);
}
}

ALTER TABLE mytable ADD COLUMN mycolumn TEXT
In your onUpgrade method, it would look something like this:
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
String upgradeQuery = "ALTER TABLE mytable ADD COLUMN mycolumn TEXT";
if (newVersion>oldVersion)
db.execSQL(upgradeQuery);
}

Example, how to drop a table and create a new table without losing data by using a temporary table:
db.execSQL("CREATE TEMPORARY TABLE temp_table (_id INTEGER PRIMARY KEY AUTOINCREMENT, col_1 TEXT, col_2 TEXT);");
db.execSQL("INSERT INTO temp_table SELECT _id, col_1, col_2 FROM old_table");
db.execSQL("CREATE TABLE new_table (_id INTEGER PRIMARY KEY AUTOINCREMENT, col_1 TEXT, col_2 TEXT, col_3 TEXT);");
db.execSQL("INSERT INTO new_table SELECT _id, col_1, col_2, null FROM temp_table");
db.execSQL("DROP TABLE old_table");
db.execSQL("DROP TABLE temp_table");

Check for the existence of database in Android [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
How to check existing database before creating new database on Android 2.2?
I have an app which check the existence of database in the start up. If not exits create a new one and if there then access the database. Can you please tell me how to check the existence of db(SQlite)?

Android helps a lot developpers to manage a database.
You should have a class like this (a single table with only 1 column) :
public class MyDBOpenHelper extends SQLiteOpenHelper {
private static final String queryCreationBdd = "CREATE TABLE partie (id INTEGER PRIMARY KEY)";
public MyDBOpenHelper(Context context, String name, CursorFactory factory, int version)
{
super(context, name, factory, version);
}
#Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL(queryCreationBdd);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
db.execSQL("DROP TABLE partie;");
db.execSQL("DELETE FROM sqlite_sequence"); //table which contains the next incremented key value
onCreate(db);
}
}
Then you simply do this :
MyDBOpenHelper databaseHelper = new MyDBOpenHelper(context, "dbname.db", null, 1);
SQLiteDatabase bdd = databaseHelper .getWritableDatabase();
If necessary, Android will create the database (call the onCreate method) or give you the one that already exists. The fourth parameter is the version of the database. If the currently created database is not the latest version, onUpgrade will be called.
EDIT : The database path will be something like this :
/data/data/fr.mathis.application/databases/dbname.db

Take a look at query-if-android-database-exists
Open your database in try block with path of the databse like:
try{
SQLiteDatabase dbe = SQLiteDatabase.openDatabase("/data/data/bangla.rana.fahim/databases/dictionary", null,0);
Log.d("opendb","EXIST");
dbe.close();
}
if an exception occurs then database doesn't exist so create it:
catch(SQLiteException e){
Log.d("opendb","NOT EXIST");
SQLiteDatabase db = openOrCreateDatabase("dictionary", MODE_PRIVATE, null);
db.execSQL("CREATE TABLE IF NOT EXISTS LIST(wlist varchar);");
db.execSQL("INSERT INTO LIST VALUES('খবর');");
db.execSQL("INSERT INTO LIST VALUES('কবর');"); //whatever you want
db.close();
}
that's it you are done :)

I use a boolean flag which is set to true when onCreate of SQLiteOpenHelper is invoked. You can find my full code here

Android: sqlite - no such table exception

I have the following code (I simplified it & removed unrelevant parts)
public class MyDatabaseManager extends SQLiteOpenHelper {
private SQLiteDatabase myDatabase;
public DatabaseManager() {
super(MyApp.getAndroidContext(), DATABASE_NAME, null, DATABASE_VERSION);
myDatabase = getWritableDatabase();
}
#Override
public void onCreate(SQLiteDatabase database) {
database.execSQL("create table t1 (t1key INTEGER PRIMARY KEY,data TEXT,num REAL,timeEnter NUMERIC);");
}
#Override
public void onUpgrade(SQLiteDatabase database, int oldVersion, int newVersion) {
}
}
Now when I run queries against this database I get sqlite - no such table exception.
My breakpoint at database.execSQL hits and it doesn't raise any exception(for example if I change the code to database.execSQL("asda") I get syntax error exception) so I think my SQL code is correct. Yet the table is not created.
I copied the database file to my pc and I looked in it with Sqlite browser and indeed my tables don't exist there. There is only one table and that is something called android_metadata. Any ideas?

Sqlite doesn't have a datatype for DATE. I would suggest changing it to an INTEGER and storing date.getTime() in it.

Change your query and try something like:
create table t1 (_id INTEGER PRIMARY KEY AUTOINCREMENT, data TEXT,num REAL,timeEnter NUMERIC);
there should be a column _id in Android Sqlite Database table and better is it should be autoincrement.

Try passing the context when you instantiate the manager by changing the constructor as follows:
public MyDatabaseManager(Context ctx) {
super(ctx, DATABASE_NAME, null, DATABASE_VERSION);
}
public openDB() throws SQLException
{
myDatabase = getWritableDatabase;
}
Now pass getApplicationContext() to the new MyDatabaseManager instance in the activity's onCreate():
MyDatabaseManager manager = new MyDataBaseManager(getApplicationContext());
manager.openDB();

Ok, I fixed the problem. There were multiple problems:
1) My create table query had problems
2) I was programatically copying the database file to the sd card at the end of the onCreate and apparently there it was not yet written. I moved it right under myDatabase = getWritableDatabase();
and it worked.
Thanks all for triying to help.

Select data from SQLite into ListArrays

I've been racking my brain on this for days and I just can't wrap my head around using SQLite databases in Android/Java. I'm trying to select two rows from a SQLite database into a ListArray (or two, one for each row. Not sure if that would be better or worse) and I just don't understand how to do it. I've tried various database manager classes that I've found but none of them do what I need and it seems that I should be able to do this simple task without the extra features I've seen in other database managers. Is there any simple way to JUST query some data from an existing SQLite database and get it into a ListArray so that I can work with it? I realize I need to copy the database from assets into the Android database path and I can handle that part. I also need to be able to modify one of the columns per row. I don't need to create databases or tables or rows. I implore someone to help me with this as I consider any code I've written (copied from the internet) to be completely useless.

You can create a method like this :
private List<MyItem> getAllItems()
List<MyItem> itemsList = new ArrayList<MyItem>();
Cursor cursor = null;
try {
//get all rows
cursor = mDatabase.query(MY_TABLE, null, null, null, null,
null, null);
if (cursor.moveToFirst()) {
do {
MyItem c = new MyItem();
c.setId(cursor.getInt(ID_COLUMN));
c.setName(cursor.getString(NAME_COLUMN));
itemsList.add(c);
} while (cursor.moveToNext());
}
} catch (SQLiteException e) {
e.printStackTrace();
} finally {
cursor.close();
}
return itemsList;
}
This will be inside your class let say MyDatabaseHelper where you will also have to declare a :
private static class DatabaseHelper extends SQLiteOpenHelper{
private final static String DATABASE_CREATE="create table " + MY_TABLE + " (id integer primary key, country string);";
public DatabaseHelper(Context context,String name, CursorFactory factory, int version){
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db){
db.execSQL(DATABASE_CREATE);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion,
int newVersion){
Log.w(TAG, "Upgrading database from version " + oldVersion
+ " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS "+ MY_TABLE);
onCreate(db);
}
}
used to open() and close() the database.