Android > SQLite

yadianna

public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//打开一个数据库，如果没有 则 create
SQLiteDatabase db = openOrCreateDatabase("test.db", Context.MODE_PRIVATE, null);
//execSQL  执行一个非SELECT和不返回数据 的SQL 语句l////
//db.execSQL("DROP TABLE IF EXISTS person");  //删除一个数据库表 如果存在
//创建person表 如果不存在 person 表
db.execSQL("CREATE TABLE IF NOT EXISTS person (_id INTEGER PRIMARY KEY AUTOINCREMENT, name VARCHAR, age SMALLINT)");
//ContentValues 以 键值 的形式存放数据
ContentValues cv = new ContentValues();
cv.put("name", "sssssssss");
cv.put("age", 9999);
//db.insert("person", null, cv);
//更新数据      类似， UPDATA person cv,  WHERE name = "sssssssss" ;
//db.update("person", cv, "name = ?", new String[]{"sssssssss"});
// 删除数据 类似， DELETE person WHERE age = "9999"
//db.delete("person","age = ?",new String[]{"9999"});
//查询  1条， WHERE age = "9999"
//Cursor c = db.rawQuery("SELECT * FROM person WHERE age >= ?", new String[]{"9999"});
//查询多条
Cursor c = db.rawQuery("SELECT * FROM person", null);
//循环输出查询结果
while (c.moveToNext()) {
int _id = c.getInt(c.getColumnIndex("_id"));
String name = c.getString(c.getColumnIndex("name"));
int age = c.getInt(c.getColumnIndex("age"));
System.out.println("_id=>" + _id + ", name=>" + name + ", age=>" + age);
}
System.out.println("更新完了");
}