Question

仅在android 9中，我重新获得所有看起来不错的异常，

例外：

android.database.sqlite.SQLiteBlobTooBigException: Row too big to fit into CursorWindow requiredPos=0, totalRows=1...

代码：

Cursor cursor = database.query(......);
    if(cursor == null || cursor.getCount() < 0) { //Here is the error
        Log.d("Error", "count : null");
        return "";
    }

编辑：

java.lang.RuntimeException: An error occurred while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:354)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:383)
at java.util.concurrent.FutureTask.setException(FutureTask.java:252)
at java.util.concurrent.FutureTask.run(FutureTask.java:271)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
at java.lang.Thread.run(Thread.java:764)

Caused by: android.database.sqlite.SQLiteBlobTooBigException: Row too big to fit into CursorWindow requiredPos=0, totalRows=1
at android.database.sqlite.SQLiteConnection.nativeExecuteForCursorWindow(Native Method)
at android.database.sqlite.SQLiteConnection.executeForCursorWindow(SQLiteConnection.java:859)
at android.database.sqlite.SQLiteSession.executeForCursorWindow(SQLiteSession.java:836)
at android.database.sqlite.SQLiteQuery.fillWindow(SQLiteQuery.java:62)
at android.database.sqlite.SQLiteCursor.fillWindow(SQLiteCursor.java:149)
at android.database.sqlite.SQLiteCursor.getCount(SQLiteCursor.java:137)

先谢谢大家

Answer 1

这对我有用，你必须把它放在你的主要活动中。

try {
    Field field = CursorWindow.class.getDeclaredField("sCursorWindowSize");
    field.setAccessible(true);
    field.set(null, 100 * 1024 * 1024); //the 100MB is the new size
    } catch (Exception e) {
       e.printStackTrace();
    }

Answer 2

尝试使用API 28上的new constructor method。也许您应该为CursorWindow设置一个受限的windowSizeBytes并尝试捕获该异常。

相关cts代码（https://android.googlesource.com/platform/cts/+/master/tests/tests/database/src/android/database/sqlite/cts/SQLiteCursorTest.java）：

    public void testRowTooBig() {
        mDatabase.execSQL("CREATE TABLE Tst (Txt BLOB NOT NULL);");
        byte[] testArr = new byte[10000];
        Arrays.fill(testArr, (byte) 1);
        for (int i = 0; i < 10; i++) {
            mDatabase.execSQL("INSERT INTO Tst VALUES (?)", new Object[]{testArr});
        }
        // Now reduce window size, so that no rows can fit
        Cursor cursor = mDatabase.rawQuery("SELECT * FROM TST", null);
        CursorWindow cw = new CursorWindow("test", 5000);
        AbstractWindowedCursor ac = (AbstractWindowedCursor) cursor;
        ac.setWindow(cw);
        try {
            ac.moveToNext();
            fail("Exception is expected when row exceeds CursorWindow size");
        } catch (SQLiteBlobTooBigException expected) {
        }
    }

其他：

自从本文最初发表以来，我们已经在中添加了新的API Android P开发人员预览版可以改善上述行为。的平台现在允许应用程序禁用窗口启发式的配置CursorWindow大小。

参考链接： https://medium.com/androiddevelopers/large-database-queries-on-android-cb043ae626e8

Answer 3

我发现如何使用length（）和substr（）仅请求1MB（CursorWindow的最大值为2MB），也许它会help。另外，您可以将context.getContentResolver().query()与仅包含_id列的选择一起使用，这样就不会加载与其他列有关的数据。

Answer 4

尝试缩放位图：

Bitmap.createScaledBitmap

SQLiteBlobTooBigException：行太大而无法容纳CursorWindow requiredPos = 0，totalRows = 1

4 个答案: