I have an android application that works as an inventory application to different stores (You can search for any electronic device according to certain specs and find which stores sell it and their location). The application comes with a local database, this database needs to get updated through a soap service to have the latest information about the electronic devices, offers and shops. The soap service will get it's data from another database hosted on the web and that gets updated from different sources through a designated website.
The problem we are facing is that we can't figure out the way to update the local database without having the user downloading the whole "online" DB from the web every time it gets updated as that would be bandwidth consuming an the DB can get as big as few MegaBytes.
We came up with the following solutions:
Create Versioned Update Scripts that will have the SQL transactions done on the online DB, the application will download them and run them to update the Local database. The issue with this solution is that if a user doesn't update the application regularly, they will have to download alot of scripts to do the update the next time they are going to update the application, and most likely it will contain a lot of junk scripts (Items get added on an early script, then gets deleted on a later on) .
Download the online DB and replace the local one with it. As mentioned above this can be pretty annoying since the DB size might be a few Megabytes.
Can someone help me with this issue?
TYI
Your best bet would be Google Cloud Messaging for Android (GCM)
http://developer.android.com/guide/google/gcm/index.html
It doesnt get any better than this. This video should get you up and running in no time dude.
http://www.youtube.com/watch?v=51F5LWzJqjg
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I'd like to receive some advice from all of you.
What is the best way for me to alert users on an update to my app? My app is a very knowledge-based & it works like a dictionary, so there will always be updates to it.
The database I have used is by DB Browser for SQLite, and they are all local database where it is uploaded into the assets folder in Android Studio.
Currently, the limitations are that:
1) it's obviously not real-time because it's stored locally;
2) every update I make to the database structure, I am required to upload the new database into the assets folder again, followed by uninstalling the old app on my phone, then run the app to install in my phone again so that the new database is overwritten.
I have read (How can I regularly update a database of content on an Android app?) & some others, and it seemed like I have to have a server, a cloud-based database & live app in market, to solve the limitations?
Is there really no way for me to overcome the limitations if I want to stick to a local database? At the same time, I kinda wish to avoid setting up a server because I am not intending to make the app live on market, and also this is just a school project I am working on and as such, I have very limited skill sets & knowledge about it and would like to make it on a school-project-based level.
Thanks in advance.
One way to do it is to connect to your local DB through local network instead of assets folder. Therefore, you can update the information by querying the local DB.
As for syncing the information between DB and your application, you should create a trigger or watcher that notify your application when the DB is updated. Therefore, your application can know when to query the DB for the updates. Another way is to just query the database periodically.
Bonus: you could move your database to a cloud-based database. Usually there are several providers that provide free database hosting up to a certain size, which should be enough for your project.
I have an architecture question. If you have a web app that is storing information on a DB server, theoretically, I should be able to use the middle tier logic for a mobile app. When the mobile app starts it can connect and populate a local SQLite DB or use JSON to store information within the mobile app. What if the mobile app also needs to work in off-line mode? Do you have it sync the next time it is connected? Do you have the mobile pull down and populate a complete DB or so it available in off-line? What are the best ways to architect a mobile app that has to go from on-line to off-line?
The simplest solution would be to put a "LastEdited" column into every table in your database and then pull query all the data which has updated since the last sync ( and you can perform a check on the index to detirmine if you need to update or insert into your own local cache. )
The ability to delete rows should actually be limited to a boolean "isDeleted" flag in this case to keep the sync process nice and simple.
If you have then the ability to edit or create rows from your app then you should keep a local table of changes to sync when you can go online and may have to implement some form of "merge" logic.
Several things you need to consider.
If your app is read only, you should implement a 'delta sync' logic in your local d. Keep a timestamp of last sync and get updates from your server. Of course, you need to consider the local db size in getting too large.
If you app is read/write, when working offline, you need to consider the two way sync especially when same record can be updated in different devices/users.
I have an android project which has a local database, when the application starts it syncs with the web service, I have a JSON file containing Countries, States and Cities of Brazil that is imported into the database as the user need this information to register the address of their customers ...
I can not get this information from the Web, because the proposal of the app is to work offline, and when you have an internet connection to send data to server.
Therefore, I was wondering if there is a way to get this data previously entered in the database and not embed them in the first inicilização, this works, but requires a lot of processing, it takes about 5 minutes on average (this is long ) to do the import.
Any solution?
Thank you!
My previous app has the same problem like this. I give you the solution that I did:
Before release your app, you should embed the latest database (imported by json, call db1) in asset folder, then copy it into application database folder (something like /data/your.package/databases) when initializing app, it only takes some seconds. By this way, you can query data and check user login/register normally.
Whenever device comes to internet, you just download the latest json data and import it into another database file (call db2) on background.If this progress doesn't have any errors, you can replace db1 file by db2 and it can work properly.
There is no other way to do that but you can minimize your payload using gzipinputstream, big cookie model to sync to your server, fast networking library called volley etc.,
Still newish to Android.
I need some advise, Should I
1. have a local sqlite DB, and have the app check for new records uptop in a mysql DB
OR
2. Publish my app with a full sqlite DB. When ever I insert new records to the full sql lite DB then publish updates?
I've been scouring the internet for some guidance. Since I am still newer to Android I wonder the difficulty in making #1 work (since I'll have to gen the php code as well).
My suggestion is:
If it's only 200 records now, it doesn't really matter if you preload it or get it from a web service (getting the data will be very quick). Usually preloaded database is better when there is a lot of data and you don't want the user to wait to long before using your App.
On the other hand if there is a lot of data, it will increase the apk size.
Create a web service method for updating the data from the server.
Create a web service method which indicate the client to delete some rows (I dont know what your application does, but usually it's needed)
What do you mean by 'uptop'? Assuming you mean 'online via an API'.
depending on the nature of your data (is is mission critical? what's the risks if it is stale? etc), it's good practice to pack static data with the app that can be referenced by the app much sooner than the updated data...the updated data is a task you run to update that stale data, and perhaps continue to run periodically to keep it updated.
It's bad practice to pack a SQLite db itself in an app, as some manufacturers do their own thing with the implementation of SQLite itself. So pack the SQL as text and create a fresh DB on the device with that.
I am developing an app in which i would need a local database.
So as per my knowledge there are two ways to do it:
First is to add pre filled database file in assets folder & make copy of local database from it the very first time app is started.
Second is using script to download it from Server for first time of app use?
First way have been pretty well answered by this guy Using your own sqlite database in android application
Can someone help how can i go with second way of download data from Server?
Should i use JSON/XML for getting that data from my Server?
Or should i go with first option since my app has only around 150 to 200 rows in the db file?
Go for the local db for the following reasons:
The users would have great on boarding experience as they can very quickly start seeing the utility of the app since you provide some data on first run without any delay that might be added when you fetch data from the server.
Do it for sure if the db doesn't increase the apk size significantly.
You must use php only if you need get information from the server, with php and json is better ...
http://www.vogella.com/articles/AndroidJSON/article.html
and if you only need share local information, only needs use MYsqLite ...
http://www.vogella.com/articles/AndroidSQLite/article.html