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Android 发布时间：2022-04-28 发布网站：大佬教程 code.js-code.com

大佬教程收集整理的这篇文章主要介绍了Android：SQLite,cursor.moveToNext()始终返回false，大佬教程大佬觉得挺不错的，现在分享给大家，也给大家做个参考。

@H_618_1@以下语句cursor.moveToNext()始终为false.我希望循环执行一次.我已经测试过查询实际返回的数据.

有谁知道是什么事吗？

String query ="SELECT(SELECT COUNT(*) FROM Table1) as count1,(SELECT COUNT(*) FROM table2) as @R_772_8023@;";

    cursor mcursor = mDb.rawQuery(query,null);

    if (mcursor != null) {
        mcursor.moveToFirst();
    }

    while (cursor.moveToNext()) {   //<---------------return false here???
        String result_0=cursor.getString(0);
    }

解决方法

我知道你已经解决了你的问题,但这是对发生的事情的@L_673_3@演练：

cursor mcursor = mDb.rawQuery(query,null);

// At this point mcursor is positioned at just before the first record.

if (mcursor != null) {
    mcursor.moveToFirst();
    // mcursor is Now poinTing at the first (and only) record
}

while (mcursor.moveToNext()) {
    String result_0=cursor.getString(0);
}

// The loop above was skipped because `.moveToNext()` caused mcursor
// to move past the last record.