_id라는 열 이름을 다시 작성했지만 getAllRows()
메서드 를 사용하여 ListView에서 데이터베이스를 실행하고 볼 때라 는 오류가 표시 (no such column: _id (code 1): , while compiling: SELECT DISTINCT _id, eventTitle, date, destination, durationTime, alarmTime FROM Event.)
됩니다.
아래는 내 코드와 내 오류 메시지입니다.
저를 도와 주시고 제 코드가 어떻게되는지 가르쳐주세요.
public class DBHandler{
private static final String TAG = "DBHandler";
//Field Names
public static final String COLUMN_ID = "_id";
public static final String COLUMN_EVENTTITLE = "eventTitle";
public static final String COLUMN_Date = "date";
public static final String COLUMN_DESTINATION = "destination";
public static final String COLUMN_DURATION = "durationTime";
public static final String COLUMN_ALARMTIME = "alarmTime";
public static final String[] ALL_KEYS = new String[]{COLUMN_ID, COLUMN_EVENTTITLE, COLUMN_Date, COLUMN_DESTINATION, COLUMN_DURATION,COLUMN_ALARMTIME};
//Column Number for each Field Name:
public static final int COL_ID = 0;
public static final int COL_EventTITLE = 1;
public static final int COL_DATE = 2;
public static final int COL_DESTINATION = 3;
public static final int COL_DURATION = 4;
public static final int COL_ALARMTIME = 5;
//Database Info:
private static final int DATABASE_VERSION = 2;
private static final String DATABASE_NAME = "SP";
public static final String TABLE_EVENT = "Event";
//SQL Statament to create database
private static final String DATABASE_CREATE_SQL =
"CREATE TABLE " + TABLE_EVENT + "(" +
COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
COLUMN_EVENTTITLE + " TEXT NOT NULL, " +
COLUMN_Date + " TEXT NOT NULL, " +
COLUMN_DESTINATION + " TEXT NOT NULL, " +
COLUMN_DURATION + " TEXT NOT NULL, " +
COLUMN_ALARMTIME + " TEXT NOT NULL" +
");";
private final Context context;
private DatabaseHelper myDBHelper;
private SQLiteDatabase db;
public DBHandler(Context ctx){
this.context = ctx;
myDBHelper = new DatabaseHelper(context);
}
public DBHandler open(){
db = myDBHelper.getWritableDatabase();
return this;
}
public void close(){
myDBHelper.close();
}
public long insertEvent(String eventtitle, String date, String destination, String duration, String alarmtime){
ContentValues contentValues = new ContentValues();
contentValues.put(COLUMN_EVENTTITLE, eventtitle);
contentValues.put(COLUMN_Date, date);
contentValues.put(COLUMN_DESTINATION, destination);
contentValues.put(COLUMN_DURATION, duration);
contentValues.put(COLUMN_ALARMTIME, alarmtime);
//Insert data into database
return db.insert(TABLE_EVENT, null, contentValues);
}
//Delete a row from the database, by rowid (primary key)
public boolean deleteRow(long rowId){
String where = COLUMN_ID + "=" + rowId;
return db.delete(TABLE_EVENT, where, null) != 0;
}
//return all data in database
public Cursor getAllRows(){
String where = null;
Cursor c = db.query(true, TABLE_EVENT, ALL_KEYS, where, null, null, null,null, null);
if(c != null){
c.moveToFirst();
}
return c;
}
//Get a specific row(by rowID)
public Cursor getRow(long rowId){
String where = COLUMN_ID + "=" + rowId;
Cursor c = db.query(true, TABLE_EVENT, ALL_KEYS, where, null, null, null, null, null);
if(c != null){
c.moveToFirst();
}
return c;
}
//Change an existing row to be equal to new data
public boolean updateEvent(long id, String eventtitle, String date, String destination, String duration,String alarmtime ){
String where = COLUMN_ID + "=" + id;
ContentValues newValues = new ContentValues();
newValues.put(COLUMN_EVENTTITLE, eventtitle);
newValues.put(COLUMN_Date, date);
newValues.put(COLUMN_DESTINATION, destination);
newValues.put(COLUMN_DURATION, duration);
newValues.put(COLUMN_ALARMTIME, alarmtime);
return db.update(TABLE_EVENT, newValues, where, null) !=0;
}
private static class DatabaseHelper extends SQLiteOpenHelper{
DatabaseHelper(Context context){
super(context, TABLE_EVENT, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db){
db.execSQL(DATABASE_CREATE_SQL);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){
Log.w(TAG, "Upgrading application's database from version" + oldVersion +
"to" + newVersion + ", which will destroy all old data!");
//Destroy old database:
db.execSQL("DROP TABLE IF EXISTS" + TABLE_EVENT);
onCreate(db);
}
}
}
오류:
android.database.sqlite.SQLiteException: no such column: _id (code 1): , while compiling: SELECT DISTINCT _id, eventTitle, date, destination, durationTime, alarmTime FROM Event
at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:1113)
at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:690)
at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58)
at android.database.sqlite.SQLiteQuery.<init>(SQLiteQuery.java:37)
at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:44)
at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1430)
at android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1277)
at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1148)
at com.howard.fyp.DBHandler.getAllRows(DBHandler.java:92)
at com.howard.fyp.TodayActivity.populateListView(TodayActivity.java:40)
at com.howard.fyp.TodayActivity.onCreateView(TodayActivity.java:26)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:1786)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:953)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1136)
at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:739)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1499)
at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:456)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5356)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
at dalvik.system.NativeStart.main(Native Method)
_id
두 번째로 열 을 추가 했습니까 ?
그런 다음 메서드 를 실행하기 위해 DATABASE_VERSION 상수 값 을 늘려야합니다 onUpgrade()
.
그러나 귀하의 onUpgrade()
방법은 이전 테이블을 파괴하지 못합니다.
db.execSQL("DROP TABLE IF EXISTS" + TABLE_EVENT);
테이블 이름 앞에 공백 이 필요합니다 .
db.execSQL("DROP TABLE IF EXISTS " + TABLE_EVENT);
또는 이전 테이블이 여전히 존재하기 때문에 새 테이블이 생성되지 않습니다.
이 기사는 인터넷에서 수집됩니다. 재 인쇄 할 때 출처를 알려주십시오.
침해가 발생한 경우 연락 주시기 바랍니다[email protected] 삭제
몇 마디 만하겠습니다