Develop Reference

Multiple Where clause in Android SQL statement

I am having some problem with the SQL statement for Android. Basically I have two where clause, bookID and userID and the SQL statement that I am having now:
public boolean updateLoan(String bookID, String userID, String currentDate) {
try {
ContentValues cv = new ContentValues();
cv.put("loanDate", currentDate);
mDb.update("loanBook", cv,
" bookID= '" + bookID + "'", null);
return true;
} catch (Exception ex) {
Log.e(TAG, ex.toString());
return false;
}
}
So I wonder how could I put two where clause in this method as currently I only can where clause by bookID. Do I simply put an "&" and continue the SQL statement?
Thanks in advance.

Do I simply put an "&" and continue the SQL statement?
Yes, use AND instead of &

Android sqlite update not done in table

Following is my code for update record done.
try {
String str_edit = edit_note.getText().toString();
Toast.makeText(getApplicationContext(), str_edit,
Toast.LENGTH_LONG).show();
Toast.LENGTH_LONG).show();
String rawQuery="UPDATE " + GlobalVariable.getstr_tbl_name()
+ " SET note = '" + str_edit + "' where name = '"
+ str + "' ";
db.execSQL(rawQuery);
} catch (Exception e) {
System.out.println(e.getMessage());
}
Code for Display:
try {
Cursor note_cursor = db.query(GlobalVariable.getstr_tbl_name(),
new String[] { "note" + " as note" }, "name" + "=?",
new String[] { GlobalVariable.getstr_food_name() }, null,
null, null);
if (note_cursor.moveToFirst()) {
int notecol = note_cursor.getColumnIndex("note");
do {
String str = note_cursor.getString(notecol);
Toast.makeText(getApplicationContext(), str,
Toast.LENGTH_LONG).show();
edit_note.setText(str);
} while (note_cursor.moveToNext());
}
}
catch (Exception e) {
System.out.println(e.getMessage());
}
I am getting all variable value i.e global variables and all but update does not reflects on table.
What wrong i am done?

whenever we try to update our database then just clean and uninstall your app then again install may be some changes not take place when we don't uninstall it if u find correct then tell other wise we will see the next

Should
int notecol = note_cursor.getColumnIndex("name");
instead be
int notecol = note_cursor.getColumnIndex("note");
since in the first block of code you are updating note..

The problem is that you try to update your DB using a rawQuery method instead of a execSql. RawQuery is intended to retrieve data from your database, while execSql lets you
Execute a single SQL statement that is NOT a SELECT or any other SQL statement that returns data.
You can also consider to use public int update (String table, ContentValues values, String whereClause, String[] whereArgs) method.

Error on using REPLACE character manipulation function on query SQLite Android

it gives me an error when I am using this key but when I use LENGTH, it works fine. I hope it is allowed on android sqlite coz it's the best way for this:
I am just trying to remove the spaces after words that will be selected from Database.
public ArrayList<String> getCorrectList() {
// TODO Auto-generated method stub
Cursor c = db.rawQuery("SELECT REPLACE(Level_1, ' ', '') FROM " + TABLE, null);
ArrayList<String> resultsList = new ArrayList<String>();
try {
if (c != null) {
if (c.moveToFirst()) {
do {
String levelData = c.getString(c
.getColumnIndex("Level_1"));
resultsList.add("" + c.getColumnIndex("Level_1"));
} while (c.moveToNext());
}
}
} catch (SQLiteException e) {
Log.e("Database", "Cannot get List (" + e + ")");
}
Log.d("array", "List: " + resultsList);
Collections.shuffle(resultsList);
return resultsList;
}

This works fine in SQLite3 shell:
e$ sqlite3
SQLite version 3.7.14.1 2012-10-04 19:37:12
Enter ".help" for instructions
Enter SQL statements terminated with a ";"
sqlite> create table t(a,b,c);
sqlite> select replace(a,' ', '') from t;
REPLACE is both a function and a command in SQLite3. Perhaps db.rawQuery is parsing the query and getting confused by REPLACE. Try this:
db.rawQuery("select rtrim(replace(Level_1, ' ', '')) FROM " + TABLE, null);

Update doesn't work sqlite android

Having problem updating a column in a table. I tried both of these solutions:
this.openDataBase();
String SQLStatement = "update " + TABLE_POSES;
SQLStatement += " set " + COLUMN_SKIP + "=" + SKIP + " Where ";
SQLStatement += COLUMN_ID + "=" + String.valueOf(skipPoseId);
myDataBase.rawQuery(SQLStatement, null);
this.close();
and this:
this.openDataBase();
ContentValues args = new ContentValues();
args.put(COLUMN_SKIP,SKIP);
myDataBase.update(TABLE_POSES, args, COLUMN_ID + "=" + String.valueOf(skipPoseId),null);
this.close();
Neither of these code snippets work and I am not getting any exceptions thrown. What am I doing wrong?

You should use the second method using update() and you should check the return value. If the value is zero, then the state of the database isn't what you expect and no rows were updated. If the row is not zero then the updating is succeeding.
If anything is wrong with your accessing the database an exception will be thrown before the update() call.
I would take advantage of the args parameter of update() like so:
myDataBase.update(TABLE_POSES, args, COLUMN_ID + " = ?", new String[]{ Long.toString(skipPoseId) });

Use update like this,
String query="UPDATE tablename SET columnname="+var+ "where columnid="+var2;
sqlitedb.execSQL(query);
Just write your update query in String query and execute.

if you use db.begintransaction() in your code you must call db.setTransactionSuccessful() before db.endtransaction() such as:
try {
SQLHelper dbHelper = new SQLHelper(this);
SQLiteDatabase db = dbHelper.getWritableDatabase();
db.beginTransaction();
...................
db.setTransactionSuccessful();
db.endTransaction();
db.close();
}
catch (Exception ex){
}

I had the exactly same issue. After much thought and debugging I saw that the WHERE condition wasn't addressing any rows of the table.
The odd thing is that the myDatabase.update command giving 1 as the return and I was understanding it as 1 row affected by the update.

How to delete a Row from the DB in android

I'm new to android ... i have developed a Database application , were i'm able to insert the textfield details , but i want to delete the specific row , i need to search by name and delete the user.
can someone help me on this :
My DB code is:
public void deleteRow(String firstname)
{
try {db.delete(TABLE_NAME,TABLE_ROW_ONE + "=?" + new String[]{firstname},null);}
catch (Exception e)
{
Log.e("DB ERROR", e.toString());
e.printStackTrace();
}
}
Activty code is :
deleteButton.setOnClickListener
(
new View.OnClickListener()
{
#Override public void onClick(View v) {deleteRow();}
}
);
private void deleteRow()
{
try
{
db.deleteRow(textFieldOne.getText().toString());
updateTable();
emptyFormFields();
}
catch (Exception e)
{
Log.e("Delete Error", e.toString());
e.printStackTrace();
}
}
textFieldOne is the first name of the user.
can someone help me on this ..

Remove the null Argument from your delete method...
do like this ---->
db.delete(TABLE_NAME,TABLE_ROW_ONE + "=?" + new String[]{ firstname });
It will work fine...

I think you've misunderstood the purpose of ? in Android+sqlite.
the ? are used as a placeholder which are then replaced with the strings you pass as the third argument to delete and other similar database functions on Android.
In your code you're setting the selection argument a combination of the selection string and the selection arguments string array.
Changing the code from
/* ... */ TABLE_ROW_ONE + "=?" + new String[]{firstname},null);
to
/* ... */ TABLE_ROW_ONE + "=?", new String[]{firstname});
should do the trick.
You can also just say
db.delete(TABLE_NAME, TABLE_ROW_ONE + "='" + firstname + "'", null);
if you want to but the purpose of the ? is to do some kind of caching with the queries so they'd be faster next time.