如何将新列添加到 Android SQLite 数据库?
问题描述:
我对 Android SQLite
数据库有一个问题.
I have one problem with Android SQLite
database.
我有一张表,其中包含一个字段.StudentFname并且该应用程序在 Android 2.3.1 上运行良好,现在如果我添加另一个字段,则我的应用程序无法正常工作.
I have one table which contains one field.StudentFname and that application is working fine with Android 2.3.1 and now if I add another field then my application is not working properly.
有懂数据库的可以帮帮我吗,
Can anyone help me who knows database very well,
答
你可以在你的 onUpgrade()
方法上使用 ALTER TABLE
函数,像这样:
you can use ALTER TABLE
function on your onUpgrade()
method, like this:
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// If you need to add a column
if (newVersion > oldVersion) {
db.execSQL("ALTER TABLE foo ADD COLUMN new_column INTEGER DEFAULT 0");
}
}
显然,SQLite 会因列定义而异.
Obviously, the SQLite will differ depending on the column definition.