java - SQLite VACUUM 命令

Question

正常情况下，我正在使用我的应用程序，超过 30000 次下载没有问题。但我看到此错误开始出现在 android 开发人员控制台(崩溃和 ANRS) 中。

by app version 3.1.1 1 100.0%

by Android version Android 2.3.3 - 2.3.7 1 100.0%

by device Blade (blade)

这是我的代码:

public  void deletetable(String Tablename){
    SQLiteDatabase db = mContext.openOrCreateDatabase(DB_NAME,
            Context.MODE_PRIVATE, null);
    db.delete(Tablename, null, null);
    db.execSQL("VACUUM"); 
}

这是报告:

java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:200)
at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:274)
at java.util.concurrent.FutureTask.setException(FutureTask.java:125)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:308)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1088)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:581)
at java.lang.Thread.run(Thread.java:1019)
Caused by: android.database.sqlite.SQLiteDiskIOException: disk I/O error: VACUUM
at android.database.sqlite.SQLiteDatabase.native_execSQL(Native Method)
at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1763)
at com.restroomgames.kpss.TestAdapter.deletetable(TestAdapter.java:194)
at com.restroomgames.kpss.TrGenelSinavAnasayfa.yenile(TrGenelSinavAnasayfa.java:395)
at com.restroomgames.kpss.TrGenelSinavAnasayfa$refreshyazi.doInBackground(TrGenelSinavAnasayfa.java:381)
at com.restroomgames.kpss.TrGenelSinavAnasayfa$refreshyazi.doInBackground(TrGenelSinavAnasayfa.java:1)
at android.os.AsyncTask$2.call(AsyncTask.java:185)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:306)
... 4 more

Answer 1

来自 VACUUM 文档:

The VACUUM command works by copying the contents of the database into a temporary database file and then overwriting the original with the contents of the temporary file. When overwriting the original, a rollback journal or write-ahead log WAL file is used just as it would be for any other database transaction. This means that when VACUUMing a database, as much as twice the size of the original database file is required in free disk space.

It may be that there is not enough free space available on disk to perform the VACUUM operation.
http://sqlite.org/lang_vacuum.html