Android sqlite: how to retrieve specific data from particular column?

Question

I am developing restaurant menu application. My app has a sqlite table which has these columns:

"id", "category", "item_name"

Contents of category column is of type string. Primary key of table is id.

I want to retrieve data of particular category.

For example, I want to retrieve item names of all items which are in category Veg and then display this result in list view.

I have tried following different queries but both are not working. Please help me.

String vg ="Veg";
Cursor mCursor = database.query(true, DATABASE_TABLE, new String[] {
           KEY_ROWID, KEY_CATEGORY, KEY_NAME,KEY_PRIZE,KEY_DESCRIPTION },
        KEY_CATEGORY + "=" + vg , null, null, null,null, null);
        if (mCursor != null) {              
                        mCursor.moveToFirst();
        }
        return mCursor;

Raw query

String query = "SELECT * FROM todo WHERE category =" + vg ;
          Cursor  cursor = database.rawQuery(query,null);
            if (cursor != null) {
                cursor.moveToFirst();
            }
            return cursor;

Answer 1

try this:

String query = "SELECT * FROM todo WHERE category='" + vg;

Cursor  cursor = database.rawQuery(query,null);

        if (cursor != null) {
            cursor.moveToFirst();
        }
        return cursor;