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POHow is onUpgrade triggered?
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copied!<p>I'm new at Android and database, I have this method in DatabaseIncomeOutcome.java class:</p> <pre><code>public DbHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); // TODO Auto-generated constructor stub } @Override public void onCreate(SQLiteDatabase db) { // TODO Auto-generated method stub db.execSQL("CREATE TABLE IF NOT EXISTS " + DATABASE_TABLE + "(" + KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + KEY_IO + " TEXT NOT NULL, " + KEY_NOTE + " TEXT NOT NULL);" ); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // TODO Auto-generated method stub db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE); onCreate(db); } } public DatabaseIncomeOutcome(Context c){ ourContext = c; } public DatabaseIncomeOutcome open(){ ourHelper = new DbHelper(ourContext); ourDatabase = ourHelper.getWritableDatabase(); return this; </code></pre> <p>when I called the method from another class</p> <pre><code> DatabaseIncomeOutcome entry = new DatabaseIncomeOutcome(this); entry.open(); </code></pre> <p>How and when the <code>onUpgrade</code> called? Is it called everytime I execute the <code>entry.open()</code>?</p> <p>I also want to add this script</p> <pre><code>if (newVersion > oldVersion) { db.execSQL("ALTER TABLE foo ADD COLUMN new_column INTEGER DEFAULT 0"); </code></pre> <p>on <code>onUpgrade</code> to add new Column,</p> <p>Then, how I should call the `onUpgrade', so I could add new column, if I might need it for future development.</p> <p>Thanks...</p>

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