SQLite in Android part 1

最新推荐文章于 2025-08-16 10:37:24 发布

原创最新推荐文章于 2025-08-16 10:37:24 发布 · 450 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#android #sqlite #database #table #construction #application

本文介绍了Android应用程序中数据库的创建与管理方式，包括如何使用SQLiteOpenHelper来创建数据库及表格，并探讨了如何通过ContentProvider使数据库变为公共访问，以便于不同组件间的数据交换。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

Some important conclusion I drawed from tutorial.

The created database will be saved in the private application folder(./data/data/YOUR_PACKAGE/database/***.db), so only the application which created the database can connect the database.
If you want to make the database to be public, then you must use content provider and create the database class(sqliteOpenHelper) as private class in content provider. Besides, the merit of using content provider lies in the easy modification of the different database systems you choosed to use.
Subclass extends SQLiteOpenHelper
private static class DatabaseHelper extends SQLiteOpenHelper{ public DatabaseHelper(Context context) { super(context, DBSV.DATABASE_NAME, null, DBSV.DATABASE_VERSION); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(DBSV.BATTARY_STATUS_TABLE.CREATE_BATTARY_STATUS_TABLE); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { Log.w(TAG, "Upgrading database from version " + oldVersion + " to " + newVersion + ", which will destroy all old data"); db.execSQL("DROP TABLE IF EXISTS "+DBSV.BATTARY_STATUS_TABLE.BATTARY_STATUS_TABLE_NAME); onCreate(
If you want to create more than one table, you should run execSQL("Create ... ") respectively. One execSQL can only create one table, other create commando will not be concerned.
private DatabaseHelper mOpenHelper; SQLiteDatabase db=mOpenHelper.getReadableDatabase; //mOpenHelper.getWriteableDatabase; db.query(); db.rawQuery(); db.insert(); db.update(); db.delete(); db.execSQL(); //details refers to android API
It is strongly recommanded that, all the static parameter for the construction of the table in database should be put in an interface or a final class, easy to make update. Personal recommandation is to use a final class. Each table will be a private class in this final class. Private classes of tables should extends BaseColumn, so they will have the attribute _id naturally!