sqlite-在Android中的使用sqlite-3

sqlite-在Android中的使用sqlite-3

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    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        
        //打开或创建test.db数据库
        SQLiteDatabase db = openOrCreateDatabase("test.db", Context.MODE_PRIVATE, null);
        db.execSQL("DROP TABLE IF EXISTS person");
        //创建person表
        db.execSQL("CREATE TABLE person (_id INTEGER PRIMARY KEY AUTOINCREMENT, name VARCHAR, age SMALLINT)");
        Person person = new Person();
        person.name = "james";
        person.age = 30;
        //插入数据
        db.execSQL("INSERT INTO person VALUES (NULL, ?, ?)", new Object[]{person.name, person.age});
        
        person.name = "lily";
        person.age = 20;
        //ContentValues以键值对的形式存放数据
        ContentValues cv = new ContentValues();
        cv.put("name", person.name);
        cv.put("age", person.age);
        //插入ContentValues中的数据
        db.insert("person", null, cv);
        
        cv = new ContentValues();
        cv.put("age", 35);
        //更新数据
        db.update("person", cv, "name = ?", new String[]{"james"});
        
        Cursor c = db.rawQuery("SELECT * FROM person WHERE age >= ?", new String[]{"33"});
        while (c.moveToNext()) {
            int _id = c.getInt(c.getColumnIndex("_id"));
            String name = c.getString(c.getColumnIndex("name"));
            int age = c.getInt(c.getColumnIndex("age"));
            Log.i("db", "_id=>" + _id + ", name=>" + name + ", age=>" + age);
        }
        c.close();
        
        //删除数据
        db.delete("person", "age < ?", new String[]{"35"});
        
        //关闭当前数据库
        db.close();
    }