I have been interested in working with a MySQL database in my iPhone or Mac projects. How is a connection performed in Objective-C?
I only had a bit of experience with PHP, but heck, that is a bit too different =/
Check this tutorial for connectivity with SQLite.
You will not be able to connect to MySQL directly from the iPhone. You must use some intermediate layer such as a Web application with PHP.
So, you will have something like this:
iPhone POSTING a request to the WebServer using HTTP
Web Server connecting to the MySQL database
Web Server returning data to the iPhone (XML, plain text)
iPhone processing the data
You can use this technique to query and insert/update/delete data.
Once I found this library for MySQL, and I am aware how it works.
It's a much better option not to deal directly with MySQL, but use Apple's Core Data API.
It allows you to manage an relational database without having to write SQL. It's very fast, very useful. Good stuff.
Try absrd which recycles connections across concurrent threads (queues).
If you want to connect to a MySQL database, use MySQL's Connector/C API library which, as Objective-C is a strict superset of C, you can use without any issues. I helped someone with the installation of it here.
Related
now I have an iPhone App and basically I want to exchange data from my database (MongoDB) on a server.
Could you please tell me exactly what I should do?
Forgive my innocence, I am a beginner in this area...Thank you very much ahead of time!!
I think you have two options to talk to mongo :
1) Use the rest interface http://www.mongodb.org/display/DOCS/Http+Interface
2) Use Objective-C driver: https://github.com/timburks/NuMongoDB
If you're not completely tied to MongoDB, have a look at CouchDB. It's essentially the same thing as MongoDB (JSON document store) but for the web. They have a nice built-in REST interface which makes database interaction in mobile/server environments very nice.
http://couchdb.apache.org/
In addition to Sid's options, you can also build your own backend that talks to mongodb, that communicates via REST (in your language of choice). This way you can pool your connections on the backend and avoid connectivity issues from the devices.
I am looking for a tutorial on how to make an iPhone app that fetches data from and writes data to a MySQL database. I've seen some other threads saying that I should make an abstraction layer so as not to connect directly to the database from my app, but I'm not sure of how to actually go about doing this. Does anyone know of any tutorials that involve creating an abstraction layer for a MySQL database or connecting a MySQL database to an iPhone app?
To clarify, I am looking for a secure method that wouldn't allow people to sniff out my MySQL host, username and password. It seems like the libraries that connect directly to MySQL from the iPhone all have this problem, but please correct me if I'm wrong.
This is a really good tutorial that covers how to communicate with MySQL from an iPhone app using PHP:
http://www.raywenderlich.com/2941/how-to-write-a-simple-phpmysql-web-service-for-an-ios-app
I know only one library, which makes possible connection from iPhone to MySQL. This is port of official MySQL C libraries created by Karl Kraft.
Author published also small portion of samples, which describes how to use this library.
UPDATE (Karl Kraft's broken link)
Instead of link above, I used an archived copy.
not up to date, but this tutorial helped me a lot:
http://codewithchris.com/iphone-app-connect-to-mysql-database/#connectiphonetomysql
Here http://blog.iosplace.com/?p=30 is a snippet that uses the original mysql client lib, and here http://www.karlkraft.com/index.php/2012/01/ is a link to a 3rd-party connector.
Here is a nice tutorial on how to connect to a database using web service layer.
From a practical perspective you could connect directly to a database from an iphone because that is a client server transaction. The problem is that you would need to expose your database server an issue that many would find very disturbing, because you would expose your server which hold your most valuable resource "your data". Of course you can implement and could be a good solution for rather small projects. But you would need to implement the layer which it would be used to connect on the iOS app, adding more complex to the matter.
Using a web service is more reliable even from the iOS developer, because there is a very extensive api for using web service, which offer great functionality (asynchronous transactions, threads management,JSON Mapping, XML Mapping) to name a few.
Use the library OHMySQL. It copes with MySQL through MySQL C API.
My App needs to connect to and grab data from a MySQL database sitting on a server. I've successfully interfaced with local SQLITE databases in my Apps, but this is the first time I've had to interface with a remote MySQL database.
I understand this process involves:
1) the iPhone App sending this request to the server
2) some sort of API gets executed and it does the actual "talking" to the Database on the server, and then it returns the query results as XML (or JSON.)
3) the iPhone then parses the returned information and uses it however it needs to.
What I need help with is step # 2 - the API. I don't know PHP, I don't know PERL - do I really have to learn one of these just to write an API? I thought that this iphone-to-remote-MySQL task would be so commonplace that such API's would already be out there, available freely - but I'm not really seeing anything.
I know Objective-C really well - but should I be using XML or JSON for this? Should I be learning PERL or PHP?
any tips or advice would be highly appreciated.
It's hard to give you a definite answer without knowing more precisely what you are looking at, but it sounds like your web service/API part should be quite light. In this case, it should be quite easy to write it in any language. If you know Objective-C well, it should be very easy to pick up some PHP or Ruby.
You mention PHP and Perl. The good thing I see with PHP is that it's available on any hosting service. For instance, with PHP you can make MySQL queries in a few lines of code.
Otherwise, if the web service lives on a machine that you own or if you have more flexibility, it might be easier to write something using Ruby and a small framework like Sinatra.
Regarding using XML or JSON to serialize the data, this will depend on what type of data your API returns. Generally, JSON will be much simpler and the support is good on both side:
- With Ruby, you can see how easy it is to use JSON here: http://flori.github.com/json/
- With Objective-C, you would use NSJSONSerialization available starting with iOS5.
Well you can talk to remote MySQL server using Objective C client directly from iphone
as show here
I want the way with the fastest execution time. I'm not feeling comfortable of using web service because i need to create separate php pages and retrieve data as xml. If you think its good to use web service please tell me why. I want to code my database queries right on my c/objective c pages.
I've been searching for libraries. I saw this sequel pro - won't i have any problems on using this - like licensing issues? I also saw this libmysqlclient of cocoa but some say its not working well. I've also read about a library developed by Karl Kraft found here http://www.karlkraft.com/index.php/2010/06/02/mysql-and-objective-c/ but don't know if i could trust this.
I would really appreciate you help.
Definitely build a web service to act as an abstraction layer to your database. Here are some significant reasons in my opinion:
Since you want speed, you will be able to add caching when using the webservice, so you will essentially eliminate the need for identical queries to run (sometimes).
If you need to change your data model later, you just have to modify the webservice backend and don't have to update your app.
You can better control security by not exposing the database to the world, and keep it safe behind the web service.
Your database credentials should not be stored in an app. What if you needed to change those?
I strongly suggest a web service. Hope this helps.
Connect to your DB by PHP and output the result as JSON
is much better and faster then xml and less coding if use JSON Framework.
and never never try to connect to your DB from your iphone because it easy to sniff out the request from iphone.
Being safe then Sorry, keep that in mind
Can you store an sqlite database remotely on a server? I am building an iphone app and all the tutorials seem to store the sqlite database on the iphone itself...
That is not advisable, as you will quickly run into concurrency problems. I would use a traditional RDMS such as MySQL or PostegreSQL in such a case.
SQLite has a useful page explaining when to use it. It says:
If you have many client programs
accessing a common database over a
network, you should consider using a
client/server database engine instead
of SQLite.
I agree with Matthew Flaschen, but if you really want to, you can connect to a sqlite db throuth an ssh tunnel. If multiple clients prefer mysql postgresql.