如何在GreenDao中使用DISTINCT

我想在SqlLite中查詢不同的行，我沒有得到如何查詢使用GreenDao庫的android。如何在GreenDao中使用DISTINCT

List<activity> activities = activityDao.queryRaw("SELECT DISTINCT "+Properties.Date_time +" FROM "+activityDao.getTablename()+" WHERE "+Properties.Contact_number+ " = "+phonenumber);

錯誤：

11-13 21:12:50.915 9320-10428/? E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #4 
               Process: com.ficean.android.ficean, PID: 9320 
               java.lang.RuntimeException: An error occured while executing doInBackground() 
                at android.os.AsyncTask$3.done(AsyncTask.java:304) 
                at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355) 
                at java.util.concurrent.FutureTask.setException(FutureTask.java:222) 
                at java.util.concurrent.FutureTask.run(FutureTask.java:242) 
                at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231) 
                at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112) 
                at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587) 
                at java.lang.Thread.run(Thread.java:818) 
               Caused by: net.sqlcipher.database.SQLiteException: near "SELECT": syntax error: , while compiling: SELECT T."_id",T."FILE_UNIQUE_ID",T."CONTACT_NUMBER",T."POND_NAME",T."REMOTE_PATH",T."LOCAL_PATH",T."IN_OUT",T."SEEN",T."STATUS",T."DATE_TIME" FROM "ACTIVITY" T SELECT DISTINCT [email protected] FROM ACTIVITY WHERE [email protected] = +919063809087 
                at net.sqlcipher.database.SQLiteCompiledSql.native_compile(Native Method) 
                at net.sqlcipher.database.SQLiteCompiledSql.compile(SQLiteCompiledSql.java:91) 
                at net.sqlcipher.database.SQLiteCompiledSql.<init>(SQLiteCompiledSql.java:64) 
                at net.sqlcipher.database.SQLiteProgram.<init>(SQLiteProgram.java:83) 
                at net.sqlcipher.database.SQLiteQuery.<init>(SQLiteQuery.java:49) 
                at net.sqlcipher.database.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:42) 
                at net.sqlcipher.database.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1758) 
                at net.sqlcipher.database.SQLiteDatabase.rawQuery(SQLiteDatabase.java:1723) 
                at org.greenrobot.greendao.database.EncryptedDatabase.rawQuery(EncryptedDatabase.java:32) 
                at org.greenrobot.greendao.AbstractDao.queryRaw(AbstractDao.java:591) 
                at com.ficean.android.ficean.Windows.SingleWindow.FilesLoad(SingleWindow.java:152) 
                at com.ficean.android.ficean.Windows.SingleWindow.access$500(SingleWindow.java:53) 
                at com.ficean.android.ficean.Windows.SingleWindow$LoadFiles.doInBackground(SingleWindow.java:138) 
                at com.ficean.android.ficean.Windows.SingleWindow$LoadFiles.doInBackground(SingleWindow.java:130) 
                at android.os.AsyncTask$2.call(AsyncTask.java:292

來源

2016-11-13 Naroju

作爲對於v3.2，有一種QueryBuilder的「獨特」方法，但我仍然試圖弄清楚。 –

您使用了錯誤的方法。除此之外，您必須將columnName包含到查詢字符串中，而不是屬性本身。

queryRaw（）只接受在WHERE子句是這樣的：

userDao.queryRaw("WHERE " + UserDao.Properties.Name.columnName + " = ?", "Jason")

如果你想自己寫整個選擇查詢，你可以使用下面這個方法：

daoSession.getDatabase().rawQuery();

它返回你一個你應該自己處理光標。

但是，如果你不想使用遊標掙扎，你可以使用這樣的事情：

userDao.queryBuilder().where(
    new WhereCondition.StringCondition(UserDao.Properties.Name.columnName + " IN " + 
     "(SELECT DISTINCT " + UserDao.Properties.Name.columnName + " FROM " + 
     UserDao.TABLENAME + " WHERE " + UserDao.Properties.Name.columnName + " = ?", 
    "Jason") 
).list();

我寫的原始字符串上面的代碼爲簡單起見：

userDao.queryBuilder().where(
    new WhereCondition.StringCondition("NAME IN (SELECT DISTINCT NAME FROM USER WHERE NAME = ?)", "Jason") 
).list();

來源

2016-11-13 17:08:10

如何在GreenDao中使用DISTINCT

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