Android的数据库错误？ [英] Android Database error?
问题描述
我有一个菜单项在我的Android应用程序，删除数据库中的所有的值，它为我调试目的使用较多，一段时间后，插入空值获得多余的。不管怎么说，我已经使用LogCat中，因为它在模拟器中运行调试我的程序，它给我一个错误：
I have a MenuItem in my Android application that deletes all the values in the database, its used more for my debugging purposes, after a while, inserting dummy values get redundant. Anyways, I have used LogCat to debug my program as it runs in the emulator and it gives me an error:
Failure 21 (out of memory) on 0x0 when preparing 'DELETE FROM <MY DBTABLE>'
我可以张贴code，但我怀疑它的code。
I can post the code but I doubt its the code.
public void deleteAll(SQLiteDatabase db) {
try {
db.execSQL("DELETE FROM " + DATABASE_TABLE);}
Log.v(TAG, "Deleting database");
db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
Log.v(TAG, "Dropping table");
onCreate(db);
Log.v(TAG, "Creating new database");}
catch (NullPointerException e) { }
catch (SQLException e) {}
}
}
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
db.execSQL("CREATE TABLE " + DATABASE_TABLE + "(ID INTEGER PRIMARY KEY AUTOINCREMENT,"
+ "LATITUDE INTEGER NOT NULL, LONGITUDE INTEGER NOT NULL, RATING INTEGER NOT NULL)");
}
这心不是我的现有功能，本来我方才：
This isnt my existing function, I had originally had just the:
db.execSQL("DELETE FROM " + DATABASE_TABLE);
但它没有工作，所以我评论它，然后想尽第一时间删除表和然后创建新表，但同样的错误。
but it didn't work, so I commented it out and then tried dropping the table first and THEN create a new table, but same error every time.
有谁知道为什么出现了这种错误，或者这个错误的方式不？
Does anyone know why this error occurred or a way for this error not to?
编辑：此方法不循环内运行，它的菜单按钮的一部分，当你选择它，调用deleteAll（）方法。一个一点要注意，我通过我做了，就在这里澄清一个适配器类调用此方法是我的code的步进式：
This method does not run inside of a loop, its part of a Menu button, that when you select it, invokes the deleteAll() method. A point to note that I call this method through an Adapter class I had made, just to clarify here is the step-through of my code:
private TrackerDBAdapter db;
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case VIEW_DATABASE:
Log.v(TAG, "Clicking on the view database menu option");
Toast.makeText(this, "This should show the databases.",
Toast.LENGTH_LONG).show();
return true;
case DELETE_VALUES:
Log.v(TAG, "Clicking on the delete values menu option");
db.deleteAll();
Toast.makeText(this, "Database is empty",
Toast.LENGTH_LONG).show();
return true;
}
然后我TrackAdapter类中。变量dbhelper是DatabaseHelper对象，它的第一个deleteAll（SQLiteDatabase DB）的问题code。
Then inside my TrackAdapter class. The variable dbhelper is a DatabaseHelper object, which has the first deleteAll(SQLiteDatabase db) code in the question.
private DatabaseHelper dbhelper;
private SQLiteDatabase db;
public void deleteAll() {
dbhelper.deleteAll(db);
}
我不记得为什么我调用一个方法，调用另一个方法。这是出于绝望也许？但不管怎么说，我要反复折腾一下，看看是否我收拾code，也许这样做我可以回答我的问题。
I do not remember why I call a method, to call another method. It was out of desperation perhaps? But anyways, I am going to fiddle around with it and see if I clean up the code, maybe by doing so I can answer my own question.
推荐答案
而不是用DELETE FROM怎么样想一个DROP TABLE？从表A删除将创建事务日志空间。而一个DROP TABLE命令不会创建事务日志空间。这可能是你错误的原因。
instead of using Delete From how about trying a DROP TABLE? A delete from Table will create transaction log space. whereas a DROP TABLE command will not create Transaction log space. This could be the cause of your error.
这篇关于Android的数据库错误？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
