全部。 我正在使用SQLite進行一項任務。 我真的很感謝能幫助我。Android SQLite查詢錯誤「無此列」
的情況是非常簡單的SQL查詢，但不工作
public class TasksDBHelper extends SQLiteOpenHelper {
private static final String LOGTAG = "Task Manager";
public static final String DB_COL_TITLE = "title";
public static String DB_COL_DESCRIPTION = "description";
public static String DB_COL_DUEDATE = "duedate";
public static String DB_COL_CATEGORY = "category";
public static String DB_COL_PRIORITY = "priority";
public static String DB_COL_BODY = "body";
public static String DB_COL_ID = BaseColumns._ID; //same as setting to "_id"
public static final String[] DB_ALL_COLUMNS = { DB_COL_ID, DB_COL_TITLE, DB_COL_DESCRIPTION, DB_COL_DUEDATE,
DB_COL_CATEGORY, DB_COL_PRIORITY};
private static final String DB_NAME = "my_tasks.db";
public static final String DB_TABLE = "tasks";
private static final int DB_VERSION = 1;
private static final String DB_TABLE_CREATE =
"CREATE TABLE tasks (" +
DB_COL_ID + " integer primary key autoincrement," +
DB_COL_TITLE + " text not null," +
DB_COL_DESCRIPTION + " text not null," +
DB_COL_DUEDATE + " text not null," +
DB_COL_CATEGORY + " text not null," +
DB_COL_PRIORITY + " text not null);";
private static TasksDBHelper INSTANCE;
public static TasksDBHelper getInstance(Context ctx){
if (INSTANCE == null)
INSTANCE = new TasksDBHelper(ctx.getApplicationContext());
return INSTANCE;
}
private TasksDBHelper(Context context) {
super(context, DB_NAME, null, DB_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
Log.d(LOGTAG, "onCreate() of the SQLite Demo");
db.execSQL(DB_TABLE_CREATE);
Log.d(LOGTAG, "Notes DB table created");
//Populate with some sample notes
ContentValues cv = new ContentValues();
for (int i = 0; i < 10; i++) {
cv.put(DB_COL_TITLE, String.format("Title : %d", i));
cv.put(DB_COL_DESCRIPTION, String.format("Body : %d", i));
cv.put(DB_COL_DUEDATE, String.format("Body : %d", i));
cv.put(DB_COL_CATEGORY, String.format("Body : %d", i));
cv.put(DB_COL_PRIORITY, String.format("Body : %d", i));
db.insert(DB_TABLE, null, cv);
}
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + DB_TABLE);
onCreate(db);
}
/////CRUD Methods
public Task createTask(Task task) {
Log.d(LOGTAG, "Calling createNote()");
SQLiteDatabase db = getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put(TasksDBHelper.DB_COL_TITLE, task.getTitle());
cv.put(TasksDBHelper.DB_COL_DESCRIPTION, task.getDescription());
cv.put(TasksDBHelper.DB_COL_DUEDATE, task.getDuedate());
cv.put(TasksDBHelper.DB_COL_CATEGORY, task.getCategory());
cv.put(TasksDBHelper.DB_COL_PRIORITY, task.getPriority());
long id = db.insert(TasksDBHelper.DB_TABLE, null, cv);
task.setId(id);
Log.d(LOGTAG, "Task created : " + id);
return task;
}
public int updateTask(Task task) {
Log.d(LOGTAG, "Calling updateNote()");
SQLiteDatabase notesDB = getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put(TasksDBHelper.DB_COL_TITLE, task.getTitle());
cv.put(TasksDBHelper.DB_COL_DESCRIPTION, task.getDescription());
cv.put(TasksDBHelper.DB_COL_DUEDATE, task.getDuedate());
cv.put(TasksDBHelper.DB_COL_CATEGORY, task.getCategory());
cv.put(TasksDBHelper.DB_COL_PRIORITY, task.getPriority());
return notesDB.update(TasksDBHelper.DB_TABLE, cv, TasksDBHelper.DB_COL_ID + "=" + task.getId(), null);
}
public ArrayList<Task> getTasks() {
Log.d(LOGTAG, "Calling getTasks()");
SQLiteDatabase notesDB = getReadableDatabase();
Cursor c = null;
ArrayList<Task> tasks = new ArrayList<Task>();
try {
//c = notesDB.query(TasksDBHelper.DB_TABLE, TasksDBHelper.DB_ALL_COLUMNS, null, null, null, null, null);
String query = String.format("SELECT _id, %s, %s, %s, %s, %s FROM %s",
TasksDBHelper.DB_COL_TITLE, TasksDBHelper.DB_COL_DESCRIPTION, TasksDBHelper.DB_COL_DUEDATE,
TasksDBHelper.DB_COL_CATEGORY, TasksDBHelper.DB_COL_PRIORITY, TasksDBHelper.DB_TABLE);
c = notesDB.rawQuery(query, null);
if ((c != null) && c.getCount() > 0) {
while(c.moveToNext())
tasks.add(getNoteFromCursor(c));
}
}
finally
{
if (c != null)
c.close();
}
return tasks;
}
public Task getTask(long rowId) {
Cursor c = null;
Task task = null;
Log.d(LOGTAG, "Calling getNote()");
SQLiteDatabase tasksDB = getReadableDatabase();
try {
c = tasksDB.query(TasksDBHelper.DB_TABLE, new String[]
{ TasksDBHelper.DB_COL_ID, TasksDBHelper.DB_COL_TITLE,
TasksDBHelper.DB_COL_DESCRIPTION, TasksDBHelper.DB_COL_DUEDATE,
TasksDBHelper.DB_COL_CATEGORY, TasksDBHelper.DB_COL_PRIORITY},
TasksDBHelper.DB_COL_ID + "=" + rowId, null, null, null, null);
if (c != null)
c.moveToFirst();
task = getNoteFromCursor(c);
return task;
} catch (Exception e) {
Log.e(LOGTAG, "Error on getNote()", e);
}
finally {
if (c != null)
c.close();
}
return task;
}
public boolean delete(long rowId) {
SQLiteDatabase notesDB = getWritableDatabase();
return notesDB.delete(TasksDBHelper.DB_TABLE, TasksDBHelper.DB_COL_ID + "=" + rowId, null) > 0;
}
private static Task getTaskFromCursor(Cursor c){
if ((c == null) || (c.getCount() == 0))
return null;
else {
Task task = new Task();
task.setId(c.getLong(c.getColumnIndex(TasksDBHelper.DB_COL_ID)));
task.setTitle(c.getString(c.getColumnIndex(TasksDBHelper.DB_COL_TITLE)));
task.setdescription(c.getString(c.getColumnIndex(TasksDBHelper.DB_COL_DESCRIPTION)));
task.setdescription(c.getString(c.getColumnIndex(TasksDBHelper.DB_COL_DUEDATE)));
task.setdescription(c.getString(c.getColumnIndex(TasksDBHelper.DB_COL_CATEGORY)));
task.setdescription(c.getString(c.getColumnIndex(TasksDBHelper.DB_COL_PRIORITY)));
return task;
}
}
}
07-06 00：35：23.621 5558-5558 /？ E/AndroidRuntime：致命例外：main 進程：com.comp3617.assignment3.chiseongoh，PID：5558 java.lang.RuntimeException：無法啓動活動 ComponentInfo {com.comp3617.assignment3.chiseongoh/com.comp3617.assignment3。 chiseongoh.DisplayTasksActivity}： android.database.sqlite.SQLiteException：no such column：title（code 1）：，while compiling：SELECT _id，title，description，duedate， category，priority FROM tasks at android.app。在android.app.ActivityThread.java:2476, 處android.app.ActivityThread.-wrap11（ActivityThread.java）在Activity.java中的ActivityThread.performLaunchActivity（ActivityThread.java:2416） at android.app.ActivityThread $ h.handleMessage（ActivityThread.java:1344） at android.os.Handler.dispatchMessage（Handler.java:102） at android.os.Looper.loop（Looper.java:148） at android.app.ActivityThread.main（ActivityThread.java:5417） at java.lang.reflect.Method.invoke（Native Method） at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java ：726） at com.android.internal.os.ZygoteInit.main（ZygoteInit.java:616） 引起：android.database.sqlite.SQLiteException：沒有這樣的列：標題（代碼 1）：，while compiling： SELECT _id，title，description，duedate， category，priorit y的在android.database.sqlite.SQLiteConnection.acquirePreparedStatement（SQLiteConnection.java:887） 在android.database.sqlite.SQLiteConnection.nativePrepareStatement（本地 法） 任務 在android.database.sqlite.SQLiteConnection.prepare（SQLiteConnection .java：498） at android.database.sqlite.SQLiteSession.prepare（SQLiteSession.java:588） at android.database.sqlite.SQLiteProgram。（SQLiteProgram.java:58） at android.database.sqlite.SQLiteQuery。 （SQLiteQuery.java:37） 在android.database.sqlite.SQLiteDirectCursorDriver.query（SQLiteDirectCursorDriver.java:44） 在android.database.sqlite.SQLiteDatabase.rawQu （在SQLiteDatabase.java:1316） at android.database.sqlite.SQLiteDatabase.rawQuery（SQLiteDatabase.java:1255） at com.comp3617.assignment3.chiseongoh.db.TasksDBHelper.getTasks（TasksDBHelper.java:128） at com.google.com。com .p3617.assignment3.chiseongoh.DisplayTasksActivity.bindListViewToNotes（DisplayTasksActivity.java:76） at com.comp3617.assignment3.chiseongoh.DisplayTasksActivity.onCreate（DisplayTasksActivity.java:71） at android.app.Activity.performCreate（Activity。 java：6237） at android.app.Instrumentation.callActivityOnCreate（Instrumentation.java:1107） at android.app.ActivityThread.performLaunchActivity（ActivityThread.java:2369） at androi d.app.ActivityThread.handleLaunchActivity（ActivityThread.java:2476） 在android.app.ActivityThread.-wrap11（ActivityThread.java） 在android.app。在android.app.android.os.Looper.loop（Looper.java:148） 處的android.os.Handler.dispatchMessage（Handler.java:102） 處的ActivityThread $ H.handleMessage（ActivityThread.java:1344） 。 ActivityThread.main（ActivityThread.java:5417） at java.lang.reflect.Method.invoke（Native Method） at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:726） at com .android.internal.os.ZygoteInit.main（ZygoteInit.java:616）
在這裏
錯誤謝謝！
謝謝！你是對的！我之前使用過一箇舊例子。謝謝！ –