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我正在編寫一個應用程序，允許用戶閱讀存儲在SQLite數據庫中的短篇小說。構建SQLite數據庫以分離可讀/寫數據
到目前爲止這麼好。
但是現在我想添加一些涉及寫入數據庫的功能（保存ScrollView的Y位置，以便用戶可以選擇它們離開的位置，爲書籤添加故事等）。
我應該將這些值添加到books表，或者我應該創建一個單獨的表user_settings的列像id（INT），story_id（INT），y_position（INT），bookmarked（布爾）？
注意：我也在考慮未來將故事存儲在非本地數據庫中的可能性。
我的另一個問題是：我是否需要將數據庫移動到某個地方纔能寫入它？我使用的SQLiteAssetHelper和數據庫目前在/assets/databases/database.db。我聽到一些關於/data/data/mypackage文件夾的討論，但我無法在我的項目中看到它。
我的數據庫設置爲當前如下：
authors
id
name
name_alphanumeric
books
id
title
author_id
collection
body
如果它是有用的，這是我DatabaseHelper至今：
public class DatabaseHelper extends SQLiteAssetHelper {
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "database9.db";
private static final String BOOKS = "books";
private static final String AUTHORS = "authors";
public DatabaseHelper (Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
// setForcedUpgrade();
}
// Getting all books
public ArrayList<Author> getAllAuthors() {
ArrayList<Author> authorList = new ArrayList<>();
// Select all query
String selectQuery = "SELECT id, name FROM " + AUTHORS + " ORDER BY name_alphabetic";
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
// create new author object
Author author = new Author();
// set ID and name of author object
author.setID(Integer.parseInt(cursor.getString(0)));
author.setName(cursor.getString(1));
// pass author object to authorList array
authorList.add(author);
} while (cursor.moveToNext());
}
// return author list
return authorList;
}
// Getting all stories
public List<Book> getAllStories(int authorID) {
List<Book> storyList = new ArrayList<>();
// Select all query
String selectQuery = "SELECT id, title FROM " + BOOKS + " WHERE author_id = " + authorID;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Book book = new Book();
book.setStoryID(Integer.parseInt(cursor.getString(0)));
book.setTitle(cursor.getString(1));
storyList.add(book);
} while (cursor.moveToNext());
}
// return contact list
return storyList;
}
// Get all collections
public List<Book> getAllCollections(int authorID) {
List<Book> collectionsList = new ArrayList<>();
// Select all query
String selectQuery = "SELECT DISTINCT collection FROM " + BOOKS + " WHERE author_id = " + authorID;
Log.i("stories", selectQuery);
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Book book = new Book();
book.setCollection(cursor.getString(0));
// Log.i("stories", cursor.getString(0));
collectionsList.add(book);
} while (cursor.moveToNext());
}
return collectionsList;
// not sure how to log collectionsList here
}
// Get story
public String getStoryBody(int storyID) {
// Log.i("stories", Integer.toString(storyID));
String storyBody = "";
// String storyBody();
// Select all query
String selectQuery = "SELECT body FROM " + BOOKS + " WHERE id = " + storyID;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
storyBody = cursor.getString(0);
} while (cursor.moveToNext());
}
return storyBody;
}
public int setScrollPosition(int scrollY, int storyID) {
String insertQuery = "UPDATE " + BOOKS + " SET scroll_position = " + scrollY + " WHERE id = " + storyID;
Log.i("insert", insertQuery);
SQLiteDatabase db = this.getWritableDatabase();
db.execSQL(insertQuery);
return 0;
}
public int getScrollPosition(int storyID) {
int scrollPosition = 0;
String selectQuery = "SELECT scroll_position FROM " + BOOKS + " WHERE id = " + storyID;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
scrollPosition = cursor.getInt(0);
} while (cursor.moveToNext());
}
return scrollPosition;
}
}