I'm in urgent need of help with a project.
I need to develop an android client, and I don't know how to get data from a database through the internet.
Could I use a socket or maybe send a http request?
Can I query the database on the client directly?
Do you mean a raw MySQL database? If you want to connect over a raw socket you would need a MySQL client on the android, I suggest looking up libraries in whatever language you are using.
Depending on what you're doing, an alternative is creating a web server that will query the database and format some results for you. You could fetch this over http and display it directly. Or you could have the server encode it into json and manipulate that on the android device.
Related
I have a script in java that works like a crawler and saves data in MySql DB. What i want to do is build a Mobile App(Andriod/ios) which will connect to mysql database retrieve results and just show it to the user.
What is the best approach to this ? I tried to use Flex UI with PHP as my server client but was hoping to know if there is a better solution ?
The fastest would be to make android fetch a page in XML, typically on the server and display its contents(If displaying contets is your desired result).
else
You need to implement a script on your server, your POST interacts with that script and inturn that script works with your database.
A typical scenario will be:
Java HTTP POST ~~~> PHP ~~~~> MySql.
PHP will as well help you encode the result in JSON and post it back to your client.
Try using jdbc or jtds library to connect android app with mysql
I used jdts library for connecting mssql db using android app.
http://jtds.sourceforge.net
For mysql jdbc might work
I am trying to learn to implement android apps to get news, promotion message, and calendar from server. What is the best and easy way to communicate with database server? using JDBC or other methods?
Thanks
Using JDBC?:
In the words of Commonsware:
Never never never use a database driver across an Internet connection,
for any database, for any platform, for any client, anywhere. That
goes double for mobile. Database drivers are designed for LAN
operations and are not designed for flaky/intermittent connections or
high latency.
On the client side (Android app), you can use SQLite to store data locally. It might not be necessary at all actually. For instance, it can be used for offline features, search, etc. For client-side, read up on this simple post
On the server side (whatever server side technology you know or want to learn), you can use whatever language, whatever database on whatever server OS you want. This part is commonly called the back-end, which will store your data while your app communicate with it through HTTP.
You can use json to parse data between server and the android device. In the server you can use jdbc with json if you are using servlets in the server.
To communicate between a server and an android device you can use JASON. See following links for some help.
http://www.androidhive.info/2012/01/android-json-parsing-tutorial/
https://www.learn2crack.com/2013/10/android-asynctask-json-parsing-example.html
https://www.learn2crack.com/2013/10/android-json-parsing-url-example.html
Also in the device to deal with data within the device you can use SQLite. And in the server you can use jdbc if you are using servelets.
To communicate with Database server You should use web service API such REST , soap
I have been learning SQLite on Android and have done some tutorials on how to use it.
There is a question that I want to ask.
Is there a way to make my app connect to my MySQL database in a remote web server of mine so that it can read data and also write data to the database?
From what I've researched, SQLite cannot be used remotely and I would need some kind of Web service in between?
It's not easy to create a connection to MySQL from Android, if it's not impossible. With that, it's also not safe if for example someone decompiles your app they have access to your whole MySQL database if you don't limit it enough.
For those reasons, you can better use a (for example) PHP webservice to which the Android application sends all their requests. An example is available at http://www.helloandroid.com/tutorials/connecting-mysql-database.
I also suggest you use Android Asynchronous Http Client so you don't have to deal with connectivity issues and AsyncTasks yourself.
You can refer to this tutorial but you do need a web-server for it.
Request mechanism
Android App ----> webserver ------> database (mysql)
Respond mechanism
Android App <---- webserver <------ database (mysql)
Android App will use JSON or other to get the data and display it
You have to use Sqlite database and web Services both. First you have to save the data in local database i.e. SQLite database and then send this data to your server using web services and vice versa.
this link for web services
and this link for SQlite will help you understand.
Thanks.
I would know how many and which are the possibile system for saving data from android application to remote sql server. I know just one way: Web service. Are there other systems?
I myself use PHP scripts and HTTP Requests. You do not want to have the app establish a direct connection to the server, because that would require database usernames and passwords sotred in the app. Use POST or GET methods to post data, and then in the PHP, echo out the results of the script and then decode them in your app.
REST + JSON. Check them out:
http://en.wikipedia.org/wiki/Representational_state_transfer
and
http://en.wikipedia.org/wiki/JSON
I have an app in android,a kind of client-server in which the client has stored some gps data in Sqlite database and once connected with server it delivers it that data which at its turn stores it in it's own database for future manipulation!
Now the problem is that I have to create a server that accepts multiple clients and I cannot find a decent example in this way.I'm not using no services in combination with it!
Both my client and server are on android!!!!
I have already did the connection between client and server,but only with one thread(I mean my server can accept only one client at this moment!)
Is this suitable?
How to implement simple threading with a fixed number of worker threads
Thank u in advance!
If server is Microsoft based, .net web service can be used that can be accessible from multiple Android clients and work with database.
Your server is not on the Android device I guess, so I don't think the question is android related.
Check out this example of multithreaded server in Java and this one as well.
To communicate with database, see the Java JDBC tutorial.
Those examples are in Java, because that's what I am used to, but any other language will fit as well.
A simple POST request from the client to the server should be good enough. Encode the data in a suitable format (JSON/XML) and send it as a POST HTTP request.
I don't understand why you want to write your own server. I would just use a PHP/Python script running with Apache to receive the POST request and store the data in a database (MySQL, PostGre).
On your Android device, you should put all your code in an AsyncTask. Android uses the standard Apache libraries to make the HTTP request.