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POI got a Cursor from database, then modify a row in the database , the data in the Cursor will change or not?
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copied!<p>Assume that I get a <code>Cursor</code> by <code>db.query()</code>.<br> Then I modify a field in a row by <code>db.update()</code>,and this row is included by <code>Cursor</code> queried before. Data in this Cursor will change or not?</p> <p>like this: </p> <pre><code>Cursor cur = db.query("[some parameter can get row 0]"); cur.moveToFirst; int a = cur.getInt(0); db.update("[some parameter can modify row 0 col 0]"); int b = cur.getInt(0); </code></pre> <p>Is (a==b) true or false ? </p> <p>====== edited 2012.10.1 =========<br> I am not a pro-programmer,and too busy to code in these days.<br> If I make you unhappy ,I am very sorry.<br> Finally , I get a holiday of a week, haha . </p> <p>I do some coding like this:</p> <pre><code>SQLiteOpenHelper h = null; SQLiteDatabase db = null; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); h=new SQLiteOpenHelper(this, "test.db", null,1){ @Override public void onCreate(SQLiteDatabase arg0) { // TODO Auto-generated method stub arg0.execSQL("CREATE TABLE t1 (_id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT )"); arg0.execSQL("INSERT INTO t1 (name) VALUES ('name_wrong')"); } @Override public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) { // TODO Auto-generated method stub }}; db=h.getWritableDatabase(); Cursor cur = db.query("t1", null, null, null, null, null, null); cur.moveToFirst(); String s1=cur.getString(1); db.execSQL("UPDATE t1 SET name = 'name_right'"); String s2=cur.getString(1); Log.d("","s1 = "+s1); Log.d("","s2 = "+s2); Log.d("","s1 == s2 is "+s1.equals(s2)); Log.d("","requery..."); cur = db.query("t1", null, null, null, null, null, null); cur.moveToFirst(); s2=cur.getString(1); Log.d("","s1 = "+s1); Log.d("","s2 = "+s2); Log.d("","s1 == s2 is "+s1.equals(s2)); } </code></pre> <p>And logcat say that: </p> <p><code>10-01 03:11:28.356: D/(1514): s1 = name_wrong</code><br> <code>10-01 03:11:28.356: D/(1514): s2 = name_wrong</code><br> <code>10-01 03:11:28.356: D/(1514): s1 == s2 is true</code><br> <code>10-01 03:11:28.356: D/(1514): requery...</code><br> <code>10-01 03:11:28.356: D/(1514): s1 = name_wrong</code><br> <code>10-01 03:11:28.356: D/(1514): s2 = name_right</code><br> <code>10-01 03:11:28.356: D/(1514): s1 == s2 is false</code> </p> <p>So I think I get the answer Thank you all guys.</p>

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