android SQLiteDatabase

数据类型

null integer real text blob

创建 extends SQLiteOpenHelper

• 构造器 SQLiteOpenHelper (Context context, String name, SQLiteDatabase.CursorFactory factory, int version)
• 第一次创建 onCreate(SQLiteDatabase db)

  String sql = "create table if not exists " + TABLE_NAME
  + " (Id integer primary key, CustomName text, OrderPrice integer, Country text)";
  sqLiteDatabase.execSQL(sql);

• 更新 onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
• 每次成功打开 onOpen(SQLiteDatabase db)


• getReadableDatabase() 　创建或者打开一个查询数据库
• getWritableDatabase()　创建或者打开一个可写数据库

操作

anroid.database.sqlite包，用于进行SQLite数据库的增，删，改，查工作

db.beginTransaction();
try {
    ...
    db.setTransactionSuccessful();
} finally {
    db.endTransaction();
}

• openOrCreateDatabase(String path, SQLiteDatabase.CursorFactory factory)
• beginTransaction(): 开始一个事务
• endTransaction(): 结束一个事务
• execSQL(String sql): 执行给定SQL语句
• close()
• query(String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy)
• rawQuery(String sql, String[] selectionArgs)
• delete(String table, String whereClause, String[] whereArgs)
• insert(String table, String nullColumnHack, ContentValues values)
• update(String table, ContentValues values, String whereClause, String[] whereArgs):

Cursor

• getCount()
• moveToFirst(), moveToNext(), isAfterLast()
• getColumnNames() getColumnIndex() getXxx()
• requery() close()

 Cursor result=db.rawQuery("SELECT _id, username, password FROM user"); 
result.moveToFirst(); 
while (!result.isAfterLast()) { 
    int id=result.getInt(0); 
    String name=result.getString(1); 
    String password =result.getString(2); 
    // do something useful with these 
    result.moveToNext(); 
} 
result.close();