理解 updateWithOnConflict [英] understanding updateWithOnConflict

问题描述

我正在使用一个简单的数据库.它有三列._id(整数主键自增)、jobnumber(文本唯一非空)和jobpart(文本非空).

I am working with a simple database. It has three columns. _id (integer primary key autoincrement), jobnumber (text unique not null) and jobpart (text not null).

一切正常，直到我尝试更新记录并输入现有的工作编号.当我这样做时，应用程序崩溃并强制关闭.

Everything works fine until I try and update a record and enter an existing jobnumber. When I do that the app crashes and I get a force close.

我正在使用 updateWithOnConflict，我认为这会导致事情正常退出并返回代码.不知道是我不明白还是我做错了什么......

I'm using updateWithOnConflict and I thought that caused things to exit gracefully and return a code. Not sure if I'm merely not understanding or if I've done something wrong...

感谢任何帮助.

更新代码片段:

    public int updateJob(long rowId, String jobnumber, String jobpart) {
        ContentValues args = new ContentValues();
        args.put(JOB_NUMBER, jobnumber);
        args.put(JOB_PART, jobpart);

        return mDb.updateWithOnConflict(JOB_TABLE, args, JOB_ROWID + "=" + rowId, null, SQLiteDatabase.CONFLICT_ROLLBACK);
    }

LogCat 的输出:

output from LogCat:

FATAL EXCEPTION: main
android.database.sqlite.SQLiteException: cannot commit - no transaction is active
at android.database.sqlite.SQLiteStatement.native_executeSql(Native Method)
at android.database.sqlite.SQLiteStatement.executeUpdateDelete(SQLiteStatement.java:89)
at android.database.sqlite.SQLiteDatabase.executeSql(SQLiteDatabase.java:1933)
at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1864)
at android.database.sqlite.SQLiteDatabase.endTransaction(SQLiteDatabase.java:688)
at android.database.sqlite.SQLiteStatement.releaseAndUnlock(SQLiteStatement.java:266)
at android.database.sqlite.SQLiteStatement.executeUpdateDelete(SQLiteStatement.java:96)
at android.database.sqlite.SQLiteDatabase.updateWithOnConflict(SQLiteDatabase.java:1829)
at cdc.gridtest.ScheduleDBAdapter.updateJob(ScheduleDBAdapter.java:325)
at cdc.gridtest.JobEdit.saveState(JobEdit.java:104)
at cdc.gridtest.JobEdit.access$0(JobEdit.java:90)
at cdc.gridtest.JobEdit$1.onClick(JobEdit.java:47)
at android.view.View.performClick(View.java:3110)
at android.view.View$PerformClick.run(View.java:11934)
at android.os.Handler.handleCallback(Handler.java:587)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:132)
at android.app.ActivityThread.main(ActivityThread.java:4123)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:491)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:841)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:599)
at dalvik.system.NativeStart.main(Native Method)

推荐答案

我认为问题在于您使用了 SQLiteDatabase.CONFLICT_ROLLBACK 标志，但您没有使用事务.您应该创建一个事务或将 CONFLICT_IGNORE 作为标志放在您的方法调用中.

I think that the problem is that you use SQLiteDatabase.CONFLICT_ROLLBACK flag but you do not use a transaction. You should either create a transaction or put CONFLICT_IGNORE as a flag in your method call.

这篇关于理解 updateWithOnConflict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！