使用，在我收到此错误之前我从未遇到过任何问题：Failed to open database '/data/user/0/com.project.projectapp.dev/databases/projectDB.db'.
android.database.sqlite.SQLiteException: not an error (code 0)
我没有对数据库文件进行任何更改，我想知道可能出现什么问题。
我尝试更改数据库版本，我尝试过模拟器和真实设备，没有任何效果。
当我没有在代码中的任何位置设置数据库文件位置时，什么可能会突然导致此错误？
编辑： 我不想去那个延伸，特别是因为错误没有指出相关的行，但我们走了：
package com.dash.dashapp.Utils;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
import com.dash.dashapp.Model.News;
import com.dash.dashapp.Model.Proposal;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
/**
* Created by sebas on 8/5/2017.
*/
public class MyDBHandler extends SQLiteOpenHelper {
public static final int DATABASE_VERSION = 20;
public static final String TABLE_NEWS = "news";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_RSS_GUID = "rss_id";
public static final String COLUMN_TITLE = "title";
public static final String COLUMN_THUMBNAIL = "image";
public static final String COLUMN_DATE = "date_pub";
public static final String COLUMN_CONTENT = "content";
public static final String TABLE_PROPOSALS = "proposal";
public static final String COLUMN_HASH = "hash"; //proposal hash [string]
public static final String COLUMN_NAME = "name"; //proposal name [string]
public static final String COLUMN_URL = "url"; //proposal URL set by the proposal owner during proposal submission [string]
public static final String COLUMN_DW_URL = "dw_url"; //URL pointing to the DashCentral proposal page [string]
public static final String COLUMN_DW_URL_COMMENTS = "dw_url_comments"; //URL pointing to the comment section on the DashCentral proposal page [string]
public static final String COLUMN_TITLE_PROP = "title_prop"; //proposal title entered by the proposal owner on DashCentral [string]
public static final String COLUMN_DATE_ADDED = "date_added"; //date, when the proposal was first seen on the network and has been added to the DashCentral database [datetime, UTC]
public static final String COLUMN_DATE_ADDED_HUMAN = "date_added_human"; //time since proposal has been added to the DashCentral database in words, eg. "6 days ago" [string]
public static final String COLUMN_DATE_END = "date_end"; //date, when proposal payouts are expected to end [datetime, UTC]
public static final String COLUMN_VOTING_DEADLINE_HUMAN = "voting_deadline_human"; //time until voting will be closed for this proposal, e.g "in 15 days" or "passed" [string]
public static final String COLUMN_WILL_BE_FUNDED = "will_be_funded"; //is true when proposal has enough yes votes to become funded [boolean]
public static final String COLUMN_REMAINING_YES_VOTES_UNTIL_FUNDING = "remaining_yes_votes_until_funding"; //amount of yes votes required for funding of this proposal [integer]
public static final String COLUMN_IN_NEXT_BUDGET = "in_next_budget"; //indicates, if proposal will be included within next budget and will be paid [boolean]
public static final String COLUMN_MONTHLY_AMOUNT = "monthly_amount"; //amount of DASH that will be paid per month [integer]
public static final String COLUMN_TOTAL_PAYMENT_COUNT = "total_payment_amount"; //amount of payment cycles this proposal was intended to run [integer]
public static final String COLUMN_REMAINING_PAYMENT_COUNT = "remaining_payment_count"; //remaining payment cycles [integer]
public static final String COLUMN_YES = "yes"; //yes votes on this proposal [integer]
public static final String COLUMN_NO = "no"; //no votes on this proposal [integer]
public static final String COLUMN_ORDER = "order_display"; //the order value should be used to sort proposals in case the JSON order is not preserved correctly. The order is defined by a reddit like algo covering the time and the upvotes and downvotes on DashCentral [integer]
public static final String COLUMN_COMMENT_AMOUNT = "comment_amount"; //amount of proposal comments posted on DashCentral [integer]
public static final String COLUMN_OWNER_USERNAME = "owner_username"; //username of the proposal owner on DashCentral [string]
private static final String DATABASE_NAME = "dashDB.db";
private static final String TAG = "MyDBHandler";
public MyDBHandler(Context context, SQLiteDatabase.CursorFactory factory) {
super(context, DATABASE_NAME, factory, DATABASE_VERSION);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NEWS);
onCreate(db);
}
@Override
public void onCreate(SQLiteDatabase db) {
String CREATE_NEWS_TABLE =
"CREATE TABLE " + TABLE_NEWS + "(" +
COLUMN_ID + " INTEGER PRIMARY KEY," +
COLUMN_RSS_GUID + " TEXT," +
COLUMN_TITLE + " TEXT," +
COLUMN_THUMBNAIL + " TEXT," +
COLUMN_DATE + " DATE," +
COLUMN_CONTENT + " TEXT" +
")";
db.execSQL(CREATE_NEWS_TABLE);
String CREATE_PROPOSAL_TABLE =
"CREATE TABLE " + TABLE_PROPOSALS + "(" +
COLUMN_HASH + " TEXT PRIMARY KEY," +
COLUMN_NAME + " TEXT," +
COLUMN_URL + " TEXT," +
COLUMN_DW_URL + " TEXT," +
COLUMN_DW_URL_COMMENTS + " DATE," +
COLUMN_TITLE_PROP + " TEXT," +
COLUMN_DATE_ADDED + " DATE," +
COLUMN_DATE_ADDED_HUMAN + " TEXT," +
COLUMN_DATE_END + " DATE," +
COLUMN_VOTING_DEADLINE_HUMAN + " TEXT," +
COLUMN_WILL_BE_FUNDED + " BOOLEAN," +
COLUMN_REMAINING_YES_VOTES_UNTIL_FUNDING + " INTEGER," +
COLUMN_IN_NEXT_BUDGET + " BOOLEAN," +
COLUMN_MONTHLY_AMOUNT + " INTEGER," +
COLUMN_TOTAL_PAYMENT_COUNT + " INTEGER," +
COLUMN_REMAINING_PAYMENT_COUNT + " INTEGER," +
COLUMN_YES + " INTEGER," +
COLUMN_NO + " INTEGER," +
COLUMN_ORDER + " INTEGER," +
COLUMN_COMMENT_AMOUNT + " INTEGER," +
COLUMN_OWNER_USERNAME + " TEXT" +
")";
db.execSQL(CREATE_PROPOSAL_TABLE);
}
// NEWS
public void addNews(News news) {
ContentValues values = new ContentValues();
values.put(COLUMN_RSS_GUID, news.getGuid());
values.put(COLUMN_TITLE, news.getTitle());
values.put(COLUMN_THUMBNAIL, news.getThumbnail());
SimpleDateFormat rssFormat = new SimpleDateFormat("EEE, dd MMM yyyy hh:mm:ss");
Date dateRSS = new Date();
try {
dateRSS = rssFormat.parse(news.getPubDate());
} catch (ParseException ex) {
ex.getMessage();
}
SimpleDateFormat sqlFormat = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
String dateSQL = sqlFormat.format(dateRSS);
values.put(COLUMN_DATE, dateSQL);
values.put(COLUMN_CONTENT, news.getContent());
SQLiteDatabase db = this.getWritableDatabase();
db.insert(TABLE_NEWS, null, values);
db.close();
}
public News findNews(String newsId) {
String query = "SELECT * FROM " + TABLE_NEWS + " WHERE " + COLUMN_RSS_GUID + "='" + newsId + "';";
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(query, null);
News news = new News();
if (cursor.moveToFirst()) {
news.setGuid(cursor.getString(1));
news.setTitle(cursor.getString(2));
news.setThumbnail(cursor.getString(3));
news.setPubDate(cursor.getString(4));
news.setContent(cursor.getString(5));
cursor.close();
} else {
news = null;
}
db.close();
return news;
}
public List<News> findAllNews(String filter) {
Log.d(TAG, "Find list news");
List<News> newsList = new ArrayList<>();
String query = "SELECT * FROM " + TABLE_NEWS;
if (filter != null) {
query += " WHERE " + COLUMN_TITLE + " LIKE '%" + filter + "%'";
}
query += " ORDER BY " + COLUMN_DATE + " DESC;";
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(query, null);
while (cursor.moveToNext()) {
News news = new News();
news.setGuid(cursor.getString(1));
news.setTitle(cursor.getString(2));
news.setThumbnail(cursor.getString(3));
news.setPubDate(cursor.getString(4));
news.setContent(cursor.getString(5));
newsList.add(news);
}
cursor.close();
db.close();
return newsList;
}
public boolean deleteNews(String newsId) {
boolean result = false;
String query = "SELECT * FROM " + TABLE_NEWS + " WHERE " + COLUMN_RSS_GUID + " = '" + newsId + "';";
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(query, null);
News news = new News();
if (cursor.moveToFirst()) {
news.setGuid(cursor.getString(1));
db.delete(TABLE_NEWS, COLUMN_RSS_GUID + " = ?",
new String[]{String.valueOf(news.getGuid())});
cursor.close();
result = true;
}
db.close();
return result;
}
public void deleteAllNews() {
SQLiteDatabase db = this.getWritableDatabase();
db.execSQL("delete from " + TABLE_NEWS);
db.close();
}
// PROPOSALS
public void addProposal(Proposal proposal) {
ContentValues values = new ContentValues();
values.put(COLUMN_HASH, proposal.getHash());
values.put(COLUMN_NAME, proposal.getName());
values.put(COLUMN_URL, proposal.getUrl());
values.put(COLUMN_DW_URL, proposal.getDw_url());
values.put(COLUMN_DW_URL_COMMENTS, proposal.getDw_url_comments());
values.put(COLUMN_TITLE_PROP, proposal.getTitle());
values.put(COLUMN_DATE_ADDED, proposal.getDate_added());
values.put(COLUMN_DATE_ADDED_HUMAN, proposal.getDate_added_human());
values.put(COLUMN_DATE_END, proposal.getDate_end());
values.put(COLUMN_VOTING_DEADLINE_HUMAN, proposal.getVoting_deadline_human());
values.put(COLUMN_WILL_BE_FUNDED, proposal.isWill_be_funded());
values.put(COLUMN_REMAINING_YES_VOTES_UNTIL_FUNDING, proposal.getRemaining_yes_votes_until_funding());
values.put(COLUMN_IN_NEXT_BUDGET, proposal.isIn_next_budget());
values.put(COLUMN_MONTHLY_AMOUNT, proposal.getMonthly_amount());
values.put(COLUMN_TOTAL_PAYMENT_COUNT, proposal.getTotal_payment_count());
values.put(COLUMN_REMAINING_PAYMENT_COUNT, proposal.getRemaining_payment_count());
values.put(COLUMN_YES, proposal.getYes());
values.put(COLUMN_NO, proposal.getNo());
values.put(COLUMN_ORDER, proposal.getOrder());
values.put(COLUMN_COMMENT_AMOUNT, proposal.getComment_amount());
values.put(COLUMN_OWNER_USERNAME, proposal.getOwner_username());
SQLiteDatabase db = this.getWritableDatabase();
db.insert(TABLE_PROPOSALS, null, values);
db.close();
}
public Proposal findProposal(String proposalHash) {
String query = "SELECT * FROM " + TABLE_PROPOSALS + " WHERE " + COLUMN_HASH + "='" + proposalHash + "';";
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(query, null);
Proposal proposal = new Proposal();
if (cursor.moveToFirst()) {
proposal.setHash(cursor.getString(0));
proposal.setName(cursor.getString(1));
proposal.setUrl(cursor.getString(2));
proposal.setDw_url(cursor.getString(3));
proposal.setDw_url_comments(cursor.getString(4));
proposal.setTitle(cursor.getString(5));
proposal.setDate_added(cursor.getString(6));
proposal.setDate_added_human(cursor.getString(7));
proposal.setDate_end(cursor.getString(8));
proposal.setVoting_deadline_human(cursor.getString(9));
proposal.setWill_be_funded(cursor.getInt(10) != 0);
proposal.setRemaining_yes_votes_until_funding(cursor.getInt(11));
proposal.setIn_next_budget(cursor.getInt(12) != 0);
proposal.setMonthly_amount(cursor.getInt(13));
proposal.setTotal_payment_count(cursor.getInt(14));
proposal.setRemaining_payment_count(cursor.getInt(15));
proposal.setYes(cursor.getInt(16));
proposal.setNo(cursor.getInt(17));
proposal.setOrder(cursor.getInt(18));
proposal.setComment_amount(cursor.getInt(19));
proposal.setOwner_username(cursor.getString(20));
cursor.close();
} else {
proposal = null;
}
db.close();
return proposal;
}
public List<Proposal> findAllProposals(String filter) {
Log.d(TAG, "Find list proposals");
List<Proposal> proposalsList = new ArrayList<>();
String query = "SELECT * FROM " + TABLE_PROPOSALS;
if (filter != null) {
query += " WHERE " + COLUMN_TITLE_PROP + " LIKE '%" + filter + "%'";
}
query += " ORDER BY " + COLUMN_DATE_END + " ASC;";
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(query, null);
while (cursor.moveToNext()) {
Proposal proposal = new Proposal();
proposal.setHash(cursor.getString(0));
proposal.setName(cursor.getString(1));
proposal.setUrl(cursor.getString(2));
proposal.setDw_url(cursor.getString(3));
proposal.setDw_url_comments(cursor.getString(4));
proposal.setTitle(cursor.getString(5));
proposal.setDate_added(cursor.getString(6));
proposal.setDate_added_human(cursor.getString(7));
proposal.setDate_end(cursor.getString(8));
proposal.setVoting_deadline_human(cursor.getString(9));
proposal.setWill_be_funded(cursor.getInt(10) != 0);
proposal.setRemaining_yes_votes_until_funding(cursor.getInt(11));
proposal.setIn_next_budget(cursor.getInt(12) != 0);
proposal.setMonthly_amount(cursor.getInt(13));
proposal.setTotal_payment_count(cursor.getInt(14));
proposal.setRemaining_payment_count(cursor.getInt(15));
proposal.setYes(cursor.getInt(16));
proposal.setNo(cursor.getInt(17));
proposal.setOrder(cursor.getInt(18));
proposal.setComment_amount(cursor.getInt(19));
proposal.setOwner_username(cursor.getString(20));
proposalsList.add(proposal);
}
cursor.close();
db.close();
return proposalsList;
}
public boolean deleteProposal(String proposalHash) {
boolean result = false;
String query = "SELECT * FROM " + TABLE_PROPOSALS + " WHERE " + COLUMN_HASH + " = '" + proposalHash + "';";
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(query, null);
Proposal proposal = new Proposal();
if (cursor.moveToFirst()) {
proposal.setHash(cursor.getString(0));
db.delete(TABLE_PROPOSALS, COLUMN_HASH + " = ?",
new String[]{String.valueOf(proposal.getHash())});
cursor.close();
result = true;
}
db.close();
return result;
}
public void deleteAllProposals() {
SQLiteDatabase db = this.getWritableDatabase();
db.execSQL("delete from " + TABLE_PROPOSALS);
db.close();
}
}
答案 0 :(得分：0)
这件事发生在我以前，我在每次使用后都没有关闭数据库，我认为它在某些时候已经损坏了。
我所做的是检查所有数据库连接并添加所有必要的代码以在每次使用后关闭它。然后，我重新安装了应用程序以再次创建数据库。
幸运与否，我再也没有遇到同样的问题。
此外，现在我看到了你的代码，你应该总是关闭你的游标，而不仅仅是当cursor.moveToFirst（）返回true时。