在SQLite数据库Android中存储数据 [英] Storing data in SQLite Database android
本文介绍了在SQLite数据库Android中存储数据的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我一直试图使用SQLite数据库在Android应用程序中存储数据.该数据库用于存储聊天应用程序的数据，还用于存储消息的各种状态，例如发送，传递，阅读等.
I have been trying to use SQLite database for storing data in Android application. The database is used to store data for a chat application and also to store various states of the messages like sent, delivered, read etc.
我在Android中面临的问题是查询正在正常运行，但是当我尝试使用下面的saveChatMessage函数插入值时，它总是返回rowID = 1.
The problem I am facing in Android is that the queries are running without error but when I try to insert the value using the saveChatMessage function below it always returns rowID = 1.
数据库没有抛出任何错误，但是当我尝试调用getAllUnsentMessages时，它将返回大小为 0 的ArrayList.
There are no errors thrown from database, but when I try to call getAllUnsentMessages, it returns an ArrayList of size 0.
我已经尝试过将在联机数据库上触发的查询，但是看起来一切正常.我不知道为什么数据没有被存储.
I have tried the queries that will be fired on online database, but things seem to work fine. I have no Idea why the data is not getting stored.
我的代码如下:
public class DatabaseManager extends SQLiteOpenHelper {
private SQLiteDatabase db;
private static final String DATABASE_NAME = "CHAT";
private static final int DATABASE_VERSION = 1;
private static final String DB_ATTRIBUTE_MESSAGE = "body";
private static final String DB_ATTRIBUTE_CLIENT_TS = "clientTS";
private static final String DB_ATTRIBUTE_DELIVERED_STATUS = "delivered";
private static final String DB_ATTRIBUTE_DEVICE_ID = "deviceID";
private static final String DB_ATTRIBUTE_FROM_ID = "fromID";
private static final String DB_ATTRIBUTE_MESSAGE_ID = "messageID";
private static final String DB_ATTRIBUTE_READ_STATUS = "readStatus";
private static final String DB_ATTRIBUTE_SENT_STATUS = "return_m";
private static final String DB_ATTRIBUTE_SERVER_TS = "serverTS";
private static final String DB_ATTRIBUTE_TO_ID = "toID";
private static final String DB_ATTRIBUTE_TOKEN = "token";
private static final String SQL_CREATE_ENTERIES = "CREATE TABLE IF NOT EXISTS " + DATABASE_NAME + " " +
"(" +
DB_ATTRIBUTE_MESSAGE + " TEXT, " + /*message*/
DB_ATTRIBUTE_CLIENT_TS +" TEXT, " + /*device Timestamp*/
DB_ATTRIBUTE_DELIVERED_STATUS + " TEXT, " + /*delivery status (-1 if Pending, 0 otherwise)*/
DB_ATTRIBUTE_DEVICE_ID + " TEXT, " + /*device ID*/
DB_ATTRIBUTE_FROM_ID + " TEXT, " + /*from ID (not necessarily Other Person)*/
DB_ATTRIBUTE_MESSAGE_ID + " TEXT, " + /*message ID i.e UUID (unique per message)*/
DB_ATTRIBUTE_READ_STATUS + " TEXT, " + /*read Status (-1 if Pending, 0 otherwise)*/
DB_ATTRIBUTE_SENT_STATUS + " TEXT, " + /*returned from Server*/
DB_ATTRIBUTE_SERVER_TS + " TEXT, " + /*server Timestamp*/
DB_ATTRIBUTE_TO_ID + " TEXT, " + /*to ID (not necessarily my ID)*/
DB_ATTRIBUTE_TOKEN + " TEXT" + /*token received from Server*/
");";
private final static DatabaseManager instance;
private static final SQLiteException DOWNGRAD_EXCEPTION = new SQLiteException(
"Database file was deleted");
static {
instance = new DatabaseManager();
instance.getDB();
}
public static DatabaseManager getInstance() {
return instance;
}
private DatabaseManager() {
super(MyApplication.getInstance(), DATABASE_NAME, null, DATABASE_VERSION);
}
/*@Override
public void onLoad() {
try {
getWritableDatabase(); // Force onCreate or onUpgrade
} catch (SQLiteException e) {
if (e == DOWNGRAD_EXCEPTION) {
// Downgrade occured
} else {
throw e;
}
}
}*/
public SQLiteDatabase getDB() {
//Perform this operation in a background thread, prefereably
if (db == null)
db = getInstance().getWritableDatabase();
return db;
}
@Override
public void onCreate(SQLiteDatabase db) {
if (db != null) {
db.execSQL(SQL_CREATE_ENTERIES);
Log.e("Create Query", SQL_CREATE_ENTERIES);
}
Log.e("Database Manager" , "DB Manager onCreate");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
//save Chat Messages from Me as well as those received from Others, for first time.
public void saveChatMsg(String msg, String myTS, String deliveredStatus, String fromID/*myID*/, String messageID,
String readStatus, String return_m, String serverTS, String toID, String token) {
if (db != null) {
// Chat Message,
// clientTS,
// deliveredStatus,
// deviceID,
// fromID,
// messageID,
// read,
// return_m,
// serverTS,
// toID,
// token
db.beginTransaction();
ContentValues values = new ContentValues();
values.put(DB_ATTRIBUTE_MESSAGE, msg);
values.put(DB_ATTRIBUTE_CLIENT_TS, myTS);
values.put(DB_ATTRIBUTE_DELIVERED_STATUS, deliveredStatus);
values.put(DB_ATTRIBUTE_DEVICE_ID, AppConstants.DEVICE_ID);
values.put(DB_ATTRIBUTE_FROM_ID, fromID);
values.put(DB_ATTRIBUTE_MESSAGE_ID, messageID);
values.put(DB_ATTRIBUTE_READ_STATUS, readStatus);
values.put(DB_ATTRIBUTE_SENT_STATUS, return_m);
values.put(DB_ATTRIBUTE_SERVER_TS, serverTS);
values.put(DB_ATTRIBUTE_TO_ID, toID);
values.put(DB_ATTRIBUTE_TOKEN, token);
// Inserting Row
long rowId = db.insert(DATABASE_NAME, null, values);
Log.e("RowID", rowId + "");
db.execSQL("INSERT INTO " + DATABASE_NAME + " VALUES (" +
"'" + msg + "', " +
"'" + myTS + "', " +
"'" + deliveredStatus + "', " +
"'" + AppConstants.DEVICE_ID + "', " +
"'" + fromID + "', " +
"'" + messageID + "'" + ", " +
"'" + readStatus + "', " +
"'" + return_m + "', " +
"'" + serverTS + "', " +
"'" + toID + "', " +
"'" + token + "'" +
");"
);
Log.e("Insert Query", "INSERT INTO " + DATABASE_NAME + " VALUES (" +
"'" + msg + "', " +
"'" + myTS + "', " +
"'" + deliveredStatus + "', " +
"'" + AppConstants.DEVICE_ID + "', " +
"'" + fromID + "', " +
"'" + messageID + "'" + ", " +
"'" + readStatus + "', " +
"'" + return_m + "', " +
"'" + serverTS + "', " +
"'" + toID + "', " +
"'" + token + "'" +
");");
if (db.inTransaction())
db.endTransaction();
} else {
Log.e("DatabaseManager", "DB is NULL");
}
}
public void updateChatStatus(String messageID, int deliveredStatus) {
//db.execSQL();
if (db != null) {
switch (deliveredStatus) {
case 0: //Sent message to server
db.beginTransaction();
db.execSQL("UPDATE " + DATABASE_NAME + " SET " + DB_ATTRIBUTE_SENT_STATUS + "='1' WHERE " + DB_ATTRIBUTE_MESSAGE_ID + "='" + messageID + "'");
if (db.inTransaction())
db.endTransaction();
break;
case 1: //Sent message to recepients device
db.beginTransaction();
db.execSQL("UPDATE " + DATABASE_NAME + " SET " + DB_ATTRIBUTE_SENT_STATUS + "='1', " + DB_ATTRIBUTE_DELIVERED_STATUS + "='1' " +
" WHERE " + DB_ATTRIBUTE_MESSAGE_ID + "='" + messageID + "'");
if (db.inTransaction())
db.endTransaction();
break;
case 2: //Recepient has read the message
db.beginTransaction();
db.execSQL("UPDATE " + DATABASE_NAME + " SET " + DB_ATTRIBUTE_SENT_STATUS + "='1', " + DB_ATTRIBUTE_DELIVERED_STATUS + "='1', " +
DB_ATTRIBUTE_READ_STATUS + "='1'" + " WHERE " + DB_ATTRIBUTE_MESSAGE_ID + "='" + messageID + "'");
if (db.inTransaction())
db.endTransaction();
break;
default:
Log.e("DatabaseManager", "Weird DeliveryStatus");
}
}
}
public List<MessagesModel> getMessages(String fromID, String toID) {
ArrayList<MessagesModel> messagesModel = new ArrayList<MessagesModel>();
Cursor cursor = db.rawQuery("SELECT * FROM " + DATABASE_NAME + " WHERE " + DB_ATTRIBUTE_FROM_ID + "='" + fromID + "'" +
" OR " + DB_ATTRIBUTE_TO_ID + "='" + fromID + "' AND " + DB_ATTRIBUTE_SENT_STATUS + "='-1' ORDER BY " + DB_ATTRIBUTE_CLIENT_TS, null);
// Chat Message,
// clientTS,
// deliveredStatus,
// deviceID,
// fromID,
// messageID,
// read,
// return_m,
// serverTS,
// toID,
// token
if (cursor == null) {
return null;
}
cursor.moveToFirst();
while (!cursor.isAfterLast()) {
MessagesModel model = new MessagesModel();
model.setMessage(cursor.getString(cursor.getColumnIndex(DB_ATTRIBUTE_MESSAGE)));
model.setTs(cursor.getString(cursor.getColumnIndex(DB_ATTRIBUTE_CLIENT_TS)));
model.setMessageUUID(cursor.getString(cursor.getColumnIndex(DB_ATTRIBUTE_MESSAGE_ID)));
model.setBlueTick(true);
model.setCode("200"); //Code 401 is used to detect that it is a history item.
model.setUser_from(cursor.getString(cursor.getColumnIndex(DB_ATTRIBUTE_FROM_ID)));
model.setUser_to(cursor.getString(cursor.getColumnIndex(DB_ATTRIBUTE_TO_ID)));
model.setType(cursor.getString(cursor.getColumnIndex(DB_ATTRIBUTE_FROM_ID)).equals(fromID) ? 0: 1);
cursor.moveToNext();
messagesModel.add(model);
}
cursor.close();
return (List<MessagesModel>) messagesModel.clone();
}
public List<MessagesModel> getAllUnsentMessages() {
ArrayList<MessagesModel> allMessages = new ArrayList<MessagesModel>();
Cursor cursor = db.rawQuery("SELECT * FROM " + DATABASE_NAME + " WHERE " + DB_ATTRIBUTE_SENT_STATUS + "='-1'", null);
if (cursor == null)
return null;
cursor.moveToFirst();
while (!cursor.isAfterLast()) {
MessagesModel model = new MessagesModel();
model.setMessage(cursor.getString(cursor.getColumnIndex(DB_ATTRIBUTE_MESSAGE)));
model.setTs(cursor.getString(cursor.getColumnIndex(DB_ATTRIBUTE_CLIENT_TS)));
model.setMessageUUID(cursor.getString(cursor.getColumnIndex(DB_ATTRIBUTE_MESSAGE_ID)));
model.setBlueTick(true);
model.setCode("200"); //Code 401 is used to detect that it is a history item. Set Code as per the status of the message
model.setUser_from(cursor.getString(cursor.getColumnIndex(DB_ATTRIBUTE_FROM_ID)));
model.setUser_to(cursor.getString(cursor.getColumnIndex(DB_ATTRIBUTE_TO_ID)));
cursor.moveToNext();
allMessages.add(model);
}
return allMessages;
}
public void execSQL(String query) {
if (db != null)
db.execSQL(query);
}
}
推荐答案
如果您正在使用事务，则需要在endTransaction()之前调用setTransactionSuccessful()进行实际提交.如果未成功设置，则更改将回滚.
If you're using transactions, you'll need to call setTransactionSuccessful() before endTransaction() to actually commit. Without setting as successful the changes are rolled back.
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