Clang GUI

use Clang GUI Front-End to Check Your Errors in Your Objective-c Code

Use the tool at this site:
http://www.karppinen.fi/analysistool/

This is Very Useful To Find Errors..just Ignore The m Prefix Warning..

How To Use Like Statement In Objective-c

To Use Like Statement In Objective-c

First Take A Temporary String like this

NSString *temp = [NSString stringWithFormat:@"%%%@%%", yourString];

now here is an example on how to use this

NSMutableString *query = [[NSMutableString alloc] initWithFormat:@"select flashCardId,flashCardText from Table where flashcardtext like '%@' and categoryId=%d",temp,categoryid];

PhoneView 2.2.2

PhoneView 2.2.2
Mac App | 9mb | Rs,Hf
PhoneView (formerly MegaPhone) is the desktop companion for iPhone and iPod Touch. This Mac OS X application which lets you use your iPhone or iPod Touch for file storage, provides note adding and editing, and easy access to your iTunes, iPhoto and notes, SMS, contacts and call history data. Convert your text, Word or PDF files into iPhone notes. It features drag and drop, making it fast and easy to move files back and forth between the Mac and iPhone.


Features:

In addition, PhoneView you can:

Create iPhone Notes on your Mac.
Store any type of data.
Access your music, videos, podcasts and photos.
Access notes, SMS, contacts and call history stored on the iPhone.
Convert your text, Word or PDF files into iPhone notes.
Move files between work and home.
Back up important data to your iPhone.
Keep useful apps and installers with you at all times.

Simple interface.
Store any type of files.
Access music, videos, podcasts and photos.
Instant access to Notes.
Easily create new Notes.
Export iPhone SMS and recent calls.
Use your iPhone for backup.
Bring your data between home and office.


More Info:
Homepage


Download Links :

Download Here





or

Here

Click Here For The Best Of Mac And Windows Softwares!

Stream Movies & TV Shows Instantly to iPhone/iPod/PSP/PC

ntroducing LuckyVidz! This site allow users to instantly stream movies and TV Shows to there iPhone, iPod, iPod Touch, PSP or anyother .MP4 supported device! The videos stream over WiFi, 3G, or EDGE networks.


Navigate the site easily!


Browse selections alphabetically!


Very informative!

Code:

www.luckyvidz.com

Don't feel like uploading or don't see your video? Use the request option on the homepage and your request will be filled.

Want to help? You can help but uploading videos, donating via PayPal, or by clicking a couple of ads. Anything is appreciated.

Download Ipod Touch/iPhone Firmwarez

hi guys, Probably a lot of u guys must be knowing about this but still for those who don't. Code: http://www.felixbruns.de/iPod/firmware/ Download any ipod/iphone firmware from this site Cheers!!

Get Cracked .ipa Applications to iPhone without OpenSSH

In this tutorial I will show you how to sync and import cracked .ipa applications from AppStore to your iPhone or iPod Touch.

Tested by me, works 100% for these devices with firmware 2.0, 2.0.1, 2.0.2 and 2.1:

iPhone
iPhone 3G
iPod Touch
iPod Touch 2G

So how to...
Before you start you need to download and install "legal" app from AppStore. If you do not do so, you will get error while trying to run cracked app.
So get an free app from AppStore
If you do now have any iTunes account, just google for it, try this sentence
"How to create iTunes account without credit card"

If you have done so, you can continue...

1. you need to have jailbreaked device(i wont tell you how to jailbrake now)
2. Cydia is required
3. in Cydia go to Manage >> Sources
4. add a new source. type exactly as is shown below

Code:

http://iphone.org.hk/apt/

5. Now go to Sections >> Tweaks and find MobileInstallation Patch
6. Install it and let the patch do its work.
7. now simply import cracked apps and games (you can find them at warez-bb of course) to iTunes and sync your device!


I hope you find this tutorial easy enough and usefull for you!
If you like it, please leave a single thank you. It wont take you a long time
THANK YOU

Code:

http://www.quickpwn.com/2008/09/jailbreak-ipod-touch-21.html

Also......This is a great place for cracked apps!

Code:

http://appulo.us/appdb/

http://www.iphonedevsdk.com/forum/iphone-sdk-development/6573-howto-customize-uikeyboard.html?0f266420

http://cocoawithlove.com/2009/04/showing-message-over-iphone-keyboard.html

http://www.iphonedevsdk.com/forum/iphone-sdk-tutorials/7350-adding-subviews-custimize-keyboard.html

http://www.ipodtouchfans.com/forums/archive/index.php/t-176944.html

http://www.ipodtouchfans.com/forums/archive/index.php/t-173786.html

http://www.ipodtouchfans.com/forums/archive/index.php/t-168191.html

iPhone SDK Tutorial: Reading data from a SQLite Database

I see many people asking for SQLite tutorials around, and since I am using SQLite for the next part in the Advanced RSS Reader Tutorial, I thought I would write up a quick tutorial on using SQLite with the iPhone SDK.

1. Project Requirements

I suggest that you have at least a basic understanding of SQLite, writing SQL statements, the XCode interface and using the terminal in OSX. If you don’t know anything about any of these topics then this tutorial probably isn’t for you.

2. Creating our SQLite database for our tutorial

We first need to create a database for use with our application. For the purposes of this tutorial we will be building a database of animals along with a little information on them and a picture.

Fire up a new Terminal window and make a new folder to store the database in, here are the commands I ran

cd /Users/lookaflyingdonkey/Documents
mkdir SQLiteTutorial
cd SQLiteTutorial
sqlite3 AnimalDatabase.sql

You should now be at a “sqlite” command prompt, this is where we will be building our database structure and entering some test data.

For our example we need the name of the animal, a short description and a link to an image. Follow the commands below to create the table and to enter some sample data.

CREATE TABLE animals ( id INTEGER PRIMARY KEY, name VARCHAR(50), description TEXT, image VARCHAR(255) );

INSERT INTO animals (name, description, image) VALUES ('Elephant', 'The elephant is a very large animal that lives in Africa and Asia', 'http://dblog.com.au/wp-content/elephant.jpg');
INSERT INTO animals (name, description, image) VALUES ('Monkey', 'Monkies can be VERY naughty and often steal clothing from unsuspecting tourists', 'http://dblog.com.au/wp-content/monkey.jpg');
INSERT INTO animals (name, description, image) VALUES ('Galah', 'Galahs are a wonderful bird and they make a great pet (I should know, I have one)', 'http://dblog.com.au/wp-content/galah.jpg');
INSERT INTO animals (name, description, image) VALUES ('Kangaroo', 'Well I had to add the Kangaroo as they are the essence of the Australian image', 'http://dblog.com.au/wp-content/kangaroo.jpg');

The first command will create the table with the required structure and the next four will insert some test data for us to work with. To ensure that you have entered the data correctly you can execute “SELECT * FROM animals;” and see if it returns the items above. Once you are confident that everything had been created successfully you can leave the sqlite command line by typing “.quit”.

3. Creating our Project

Now that our database is all ready to go we need to setup our X-Code project.

Start off by creating a new “Navigation-Based Application”.

Give your Project a name, I called mine “SQLiteTutorial”.

Now set your screen layout to how you prefer it, I suggest making the window as large as possible, and making the code view as tall as possible by dragging the horizontal slider to the top. This will allow you the most room to move when building your application.

Now its time to create the required classes and views for our application, we will start off by making our views.

Right Click on the “Resources” folder in the left hand pane and click “Add File”, we want to create a new “View XIB” under the “User Interfaces” group.

We now need to give it a name, to stick the Apple’s naming conventions we are going to call it “AnimalViewController.xib”, Now Click “Finish”.

Now we need to create two classes, the first one will represent an animal, right click on the “Classes” folder in the left hand pane, click “Add > New File…”, choose the “NSObject subclass” template under the “Cocoa Touch Classes” group and name it “Animal”.

The second class will be for our AnimalsViewController, right click on the “Classes” folder in the left hand pane, click “Add > New File…”, choose the “UIViewController subclass” under the “Cocoa Touch Classes” group and name it “AnimalViewController”.

4. Adding SQLite Framework and our Animal Database

Now that we have created all of our views and classes it is time to start the real grunt work.

First off we need to include the SQLite libraries so our application can utilise them. To do this you will need to right click on the “Frameworks” folder in the left hand pane, then click on “Add > Existing Frameworks…”, then navigate to “/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS2.0.sdk/usr/lib/” and double click the “libsqlite3.0.dylib” file. A popup will appear, just click “Add” and the library will be added to your project.

We also need to add our database we created earlier to the Resources folder, to do this simply right click on the “Resources” folder, click “Add > Existing Files…”, navigate to the location you created the database in then double click on the AnimalDatabase.sql file. Another popup will appear, just click add.

All done with the importing, time to code!

5. The Coding begins!

We are going to start the coding by building our “Animal” object, every animal will have 3 properties, a name, a description and an image URL.

Open up the “Animal.h” file from the “Classes” folder and edit its contents to look like below,

#import 

@interface Animal : NSObject {
 NSString *name;
 NSString *description;
 NSString *imageURL;
}

@property (nonatomic, retain) NSString *name;
@property (nonatomic, retain) NSString *description;
@property (nonatomic, retain) NSString *imageURL;

-(id)initWithName:(NSString *)n description:(NSString *)d url:(NSString *)u;

@end

Most of the above code should be pretty familiar to you, the only thing that may not be is the initWithName line, this line will allow us to create a new object with the required data, we could have used the default init function, but it will be easier for us to define our own.

Now we will actually have to implement the Animal Object, open up the “Animal.m” file and edit its contents to look like below:

#import "Animal.h"

@implementation Animal
@synthesize name, description, imageURL;

-(id)initWithName:(NSString *)n description:(NSString *)d url:(NSString *)u {
 self.name = n;
 self.description = d;
 self.imageURL = u;
 return self;
}
@end

The above code should be pretty easy to read as well, it basically stores the supplied data from the initWithName function and return the object (self).

Now its time to setup the Application delegate to access the database.

Open up the “SQLiteTutorialAppDelegate.h” and edit its contents to look like below:

#import 
#import  // Import the SQLite database framework

@interface SQLiteTutorialAppDelegate : NSObject  {

   UIWindow *window;
   UINavigationController *navigationController;

 // Database variables
 NSString *databaseName;
 NSString *databasePath;

 // Array to store the animal objects
 NSMutableArray *animals;
}

@property (nonatomic, retain) IBOutlet UIWindow *window;
@property (nonatomic, retain) IBOutlet UINavigationController *navigationController;
@property (nonatomic, retain) NSMutableArray *animals;

@end

What we are doing here is importing the SQLite database framework and creating some variables for storing the database details and an array of animal objects.

Now open up the “SQLiteTutorialAppDelegate.m” file and edit its contents to look like below:

#import "SQLiteTutorialAppDelegate.h"
#import "RootViewController.h"
#import "Animal.h" // Import the animal object header

@implementation SQLiteTutorialAppDelegate

@synthesize window;
@synthesize navigationController;
@synthesize animals; // Synthesize the aminals array

- (void)applicationDidFinishLaunching:(UIApplication *)application {
 // Setup some globals
 databaseName = @"AnimalDatabase.sql";

 // Get the path to the documents directory and append the databaseName
 NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
 NSString *documentsDir = [documentPaths objectAtIndex:0];
 databasePath = [documentsDir stringByAppendingPathComponent:databaseName];

 // Execute the "checkAndCreateDatabase" function
 [self checkAndCreateDatabase];

 // Query the database for all animal records and construct the "animals" array
 [self readAnimalsFromDatabase];

 // Configure and show the window
 [window addSubview:[navigationController view]];
 [window makeKeyAndVisible];
}

- (void)applicationWillTerminate:(UIApplication *)application {
 // Save data if appropriate
}

- (void)dealloc {
 [animals release];
 [navigationController release];
 [window release];
 [super dealloc];
}

-(void) checkAndCreateDatabase{
 // Check if the SQL database has already been saved to the users phone, if not then copy it over
 BOOL success;

 // Create a FileManager object, we will use this to check the status
 // of the database and to copy it over if required
 NSFileManager *fileManager = [NSFileManager defaultManager];

 // Check if the database has already been created in the users filesystem
 success = [fileManager fileExistsAtPath:databasePath];

 // If the database already exists then return without doing anything
 if(success) return;

 // If not then proceed to copy the database from the application to the users filesystem

 // Get the path to the database in the application package
 NSString *databasePathFromApp = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:databaseName];

 // Copy the database from the package to the users filesystem
 [fileManager copyItemAtPath:databasePathFromApp toPath:databasePath error:nil];

 [fileManager release];
}

-(void) readAnimalsFromDatabase {
 // Setup the database object
 sqlite3 *database;

 // Init the animals Array
 animals = [[NSMutableArray alloc] init];

 // Open the database from the users filessytem
 if(sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) {
  // Setup the SQL Statement and compile it for faster access
  const char *sqlStatement = "select * from animals";
  sqlite3_stmt *compiledStatement;
  if(sqlite3_prepare_v2(database, sqlStatement, -1, &compiledStatement, NULL) == SQLITE_OK) {
   // Loop through the results and add them to the feeds array
   while(sqlite3_step(compiledStatement) == SQLITE_ROW) {
    // Read the data from the result row
    NSString *aName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 1)];
    NSString *aDescription = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 2)];
    NSString *aImageUrl = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 3)];

    // Create a new animal object with the data from the database
    Animal *animal = [[Animal alloc] initWithName:aName description:aDescription url:aImageUrl];

    // Add the animal object to the animals Array
    [animals addObject:animal];

    [animal release];
   }
  }
  // Release the compiled statement from memory
  sqlite3_finalize(compiledStatement);

 }
 sqlite3_close(database);

}

@end

Now I know that may look like a fair bit of code and it probably also looks quite scary! But really it is quite simple and I have tried to comment nearly every line to describe to you what the line does and why it is there.

The checkAndCreateDatabase function checks to see if we have already copied our database from the application bundle to the users filesystem (in their documents folder), if the database hasn’t already been created or it has been removed for some reason it will be recreated from the default database.

Next the readAnimalsFromDatabase function will make a connection to the database that is stored in the users documents folder, and then executes the SQL statement “SELECT * FROM animals”. It will then go through each row that is returned and it will extract the name, description and imageURL from the result and build an Animal object for each. You will see the “sqlite3_column_text” function used here, there are many more of these for returning other field types such as “sqlite3_column_int” for integers, “sqlite3_column_blob” for blobs or “sqlite3_column_value” to get an unknown value.

Now that we have the data in our array and we have it in our known format we are ready to start displaying it.

Open up the “RootViewController.m” file and edit the numberOfRowsInSection to look like the following:

SQLiteTutorialAppDelegate *appDelegate = (SQLiteTutorialAppDelegate *)[[UIApplication sharedApplication] delegate];
return appDelegate.animals.count;

What this does is it creates a link to the application delegate, and then the second line returns the size f the animals array in out Application delegate, this array was filled previously from the SQLite database.

Now in the cellForRowAtIndexPath function you will need at change it to look like the following:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

   static NSString *CellIdentifier = @"Cell";

   UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
   if (cell == nil) {
       cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:CellIdentifier] autorelease];
   }

   // Set up the cell
   SQLiteTutorialAppDelegate *appDelegate = (SQLiteTutorialAppDelegate *)[[UIApplication sharedApplication] delegate];
 Animal *animal = (Animal *)[appDelegate.animals objectAtIndex:indexPath.row];

 [cell setText:animal.name];
 return cell;
}

We pretty much just added 3 lines under the “// Set up the cell” line, the first one is the same as we added previously to access the application delegate. The second line creates a new Animal object based on the array from the application delegate, it will be used to create a row for each individual record in the database. On the final line we are just setting the text of the cell to the name field from the Animal object.

You can now run the program and you should see a table view with the 4 animals we added to the database, if you added more than my default animals you should see them in here as well.

We will now setup the AnimalViewController, open up the “AnimalViewController.h” file and edit its contents to below:

#import 

@interface AnimalViewController : UIViewController {
 IBOutlet UITextView *animalDesciption;
 IBOutlet UIImageView *animalImage;
}

@property (nonatomic, retain) IBOutlet UITextView *animalDesciption;
@property (nonatomic, retain) IBOutlet UIImageView *animalImage;

@end

What we are doing above is adding an outlet for the description and image for the Animal, we will use these later on when we link the view up.

Now open up the “AnimalViewController.m” file and add a synthesize call for for the description and image, this will go under the “@implementation AnimalViewController” line, like so:

#import "AnimalViewController.h"

@implementation AnimalViewController

@synthesize animalDesciption, animalImage;

Now it is time to make the detailed view page appear when you select a record. Open up the “AnimalViewController.xib” file from the resources folder and the interface builder should appear.

The first thing we need to do is to set the File’s Owner Class to AnimalViewController, this is done by selecting the “File’s Owner” item in the main window and then clicking Tools > Identity Inspector in the top menu, and then selecting AnimalViewController from the class dropdown.

Your inspector window should now look like this:

We are going to be using a UITextView for the description (as it will allow for word wrapping and scrolling in the case that the description is quite large) and a UIImageView to display the image. I have laid mine out like below:

Now that we have everything laid out it is time to link them all up, start by holding control and click+drag from the “File’s Owner” to the “View” objects, a little gray menu will appear and you will need to select view. Now hold control and click+drag from the “File’s Owner” to the UITextView in the layout window, you should see “animalDescription” in the popup list, select it. Repeat this process for the UIImageView and you should see animalImage appear, select it also.

Now save the interface and close the interface builder.

Nearly done! All we have to do now is to setup the code for when a user presses on a record in the table view.

Open up the “RootViewController.h” file and edit its contents to below:

#import 
#import "AnimalViewController.h"

@interface RootViewController : UITableViewController {
 AnimalViewController *animalView;
}

@property(nonatomic, retain) AnimalViewController *animalView;

@end

We are creating an instance of the AnimalViewController to be used bu the RootViewController when a user presses on an item.

Now open up the “RootViewController.m” file and edit the top part of the file to look like below:

#import "RootViewController.h"
#import "SQLiteTutorialAppDelegate.h"
#import "Animal.h"

@implementation RootViewController
@synthesize animalView;

This will just synthesize the animalView that we just added.

First up lets set the default title of our view, to do this you need to uncomment the viewDidLoad function, and edit it to below:

- (void)viewDidLoad {
   [super viewDidLoad];
   // Uncomment the following line to add the Edit button to the navigation bar.
   // self.navigationItem.rightBarButtonItem = self.editButtonItem;

 self.title = @"My Zoo";
}

We also need to edit the didSelectRowAtIndexPath

function in this file, edit it to look like below:

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
   // Navigation logic -- create and push a new view controller
 SQLiteTutorialAppDelegate *appDelegate = (SQLiteTutorialAppDelegate *)[[UIApplication sharedApplication] delegate];
 Animal *animal = (Animal *)[appDelegate.animals objectAtIndex:indexPath.row];

 if(self.animalView == nil) {
  AnimalViewController *viewController = [[AnimalViewController alloc] initWithNibName:@"AnimalViewController" bundle:nil];
  self.animalView = viewController;
  [viewController release];
 }

 // Setup the animation
 [self.navigationController pushViewController:self.animalView animated:YES];
 // Set the title of the view to the animal's name
 self.animalView.title = [animal name];
 // Set the description field to the animals description
 [self.animalView.animalDesciption setText:[animal description]];
 // Load the animals image into a NSData boject and then assign it to the UIImageView
 NSData *imageData = [NSData dataWithContentsOfURL:[NSURL URLWithString:[animal imageURL]]];
 UIImage *animalImage = [[UIImage alloc] initWithData:imageData cache:YES];
 self.animalView.animalImage.image = animalImage;

}

What we are doing here is checking to see if the animalView object has already been created, if not then create it.

The next few lines are used to setup the animation (slide from right to left) and to set the actual data fields to those of the selected animal.

Now you should be ready to fire up the application and see it in all its glory.

You should see your windows looking like below.

5. Project Files

Here are the source files for this project: Download the project source files

If you have any questions or comments please feel free to post them here and I will try to get back to you ASAP. Also keep your eye out for my second part to the advanced RSS Reader tutorial, it will be using TouchXML, SQLite, UIWebview and more!

original post is here

http://dblog.com.au/iphone-development-tutorials/iphone-sdk-tutorial-reading-data-from-a-sqlite-database/comment-page-3/#comment-3095

iPhone SQLite Database Basics - Part 2

After writing the article on iPhone SQLite Database Basics, I received lots of followup questions and comments, some of which I will discuss here.

SQLite Database Creation

In my first article I wrote that the easiest way to work with SQLite databases on the mac was the SQLite extension for Firefox.

Since then, my attention has been brought to Menial’s Base application. This is the application that I now use for all of my SQLite work. It is super fast, and has an interface that is extremely easy to use. It also has a lot of nice touches that make it more Mac-like than using a Firefox extension. If you’re doing SQLite work on the Mac, I strongly recommend that you check it out.

Making a Writable Copy of the Database

In the first part of this tutorial, I mentioned that if you needed to write to your database you needed to copy it to a location that you could write to.

A couple of people have asked how to do this. To answer that, I first want to talk a little bit about how to control SQLite access in Cocoa applications. There are really three ways to do this:

1. Have DB access code in each class that needs it (bad)
2. Have you application delegate handle all DB access for you (better)
3. Use a singleton object for your DB access (best)

For more about the tradeoffs between application delegate usage and singleton objects see this post from Cocoa with Love.

If you are using the singleton pattern, then you can make a writable copy of your database in your singleton object’s allocation method, using something like this:

1. -(NSString*)createWriteableDB
2. {
3. // See if writeable database already exists
4. NSFileManager *fileManager = [NSFileManager defaultManager];
5. NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
6. NSString *documentsDirectory = [paths objectAtIndex:0];




7. NSString *readOnlyDBPath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:self.databaseFileName];
8. NSString *writableDBPath = [[documentsDirectory stringByAppendingPathComponent:self.databaseFileName] retain];




9. // First time install
10. if(![fileManager fileExistsAtPath:writableDBPath])
11. {
12. if(![fileManager copyItemAtPath:readOnlyDBPath toPath:writableDBPath error:&self.lastError])
13. {
14. NSAssert1(0, @”Failed to create writable database file with message ‘%@’.”, [self.lastError localizedDescription]);
15. return nil;
16. }
17. }




18. return [writableDBPath autorelease];
19. }

A couple of important things to note here:

If you have a very large database and the things that you need to allow the user to update, (i.e. bookmarks, or annotations) are small in comparison, it may be better for you to have two databases files, one that contains the data that won’t change, and the other that contains the data used for annotations. This way you won’t have two large copies of the database on the user’s device.

This will of course have a large impact on your query design, and some database purists may be lining up to lynch me, but as I mentioned in the first article, there are some SQLite considerations that are unique to mobile devices like the iPhone.

Another thing to consider is versioning. You need to be very careful how you handle application updates that change the database structure and/or content when you are allowing the user to write data (that presumably they want to persist between updates).

One way to handle this is to simply have a table in your writable database called “Version” which contains one row and one column with the version number of the database schema.

Then in the above code you can add some logic to transfer the data from a pervious schema version to the new writable database file.

Third Party SQLite Wrappers

There are lots of SQLite wrappers available for iPhone development. I’ve never used any so I can’t say if any one is better than another. If the idea of using c-based SQLite calls makes you anxious, you may want to check them out.

Security

Someone suggested that I point out that SQLite databases on the iPhone aren’t really secure. I’m not a database security expert, but that statement is true of databases on any platform. The database is only as secure as the device itself. If someone gets ahold of your iPhone, they can most likely get the data off of it.

iPhone SQLite Database Basics

In celebration of the lifting of the NDA on the iPhone SDK, I decided to write a tutorial on using SQLite on the iPhone.

This tutorial covers the basics of SQLite database creation, things to consider in the design of the database, and some particular things to be aware of when deploying these types of applications to the iPhone.

Once you have finished with these basics, take a look at the SQLiteBooks sample code from the iPhone dev center for details on how to interface with the database from your code.

Step 1: Create a SQLite Database File

There are lots of ways to create a SQLite database file. The easiest way that I have found is to download the SQLite Firefox extension, which provides a GUI to create and manage your SQLite database. The rest of this tutorial will assume you have that extension installed.

In this tutorial we’ll be creating a recipe application, so we are naming our database “recipes”.

To create the database:

1. Click the “New Database” toolbar button.
2. Enter the name of the database file.
3. Click OK.

You will then be prompted for a location to save the database. The ideal place is in the directory of your XCode project.

Step 2: Create the Database Schema

Now we are going to setup our database tables. This will be a very simple database with two tables:

There are entire textbooks about “proper” database design and if you are developing a super large-scale ultra robust data warehouse app, you might want to look them over. However rather than make your eyes glaze over with the merits of third normal form, let me just share a few guidelines that I picked up during several years as a DBA/Database application developer:

1. Every table should mirror an object, with each non-calculated object property mapping directly to a table field.
2. In addition to the object properties, every table should have an integer field that is autofilled with a unique identifier (commonly know as the primary key).
3. Every table that is dependent on a parent table should have a way to refer back to its parent. (This is sometimes called a Foreign Key)

In our application we’re going to have two model objects. A Recipe object, and an Ingredient object. Each recipe object can have 1 or more ingredient child objects. (The blue arrow in the above diagram signifies this, and is called a 1-to many relationship).

The Recipe object has a name and description property. These are both strings, and these map to database fields of type VarChar (meaning Variable length Character string). In addition, the Recipes table has a Recipe_ID field of type Integer. This field is the primary key of the Recipes table.

The ingredient object in our simple application only has one property, Description. Since this is a string it also maps to a VarChar field. Our Ingredients table also has a primary key (Ingredient_ID) which gives us a way to refer to a specific ingredient.

Finally, the Recipe_ID field in the Ingredients table is our foreign key back to the Recipes table. Using that key you can look at any ingredient and know what Recipe it belongs to. More commonly an application will use that key to get all of the ingredients that belong to a specific recipe.

To create the Recipes table, click the “New Table” toolbar button and enter the information as seen below:

Notice that we check the Primary Key and Autoinc checkboxes for the Recipe_ID field. The Primary Key checkbox tells SQLite to treat this field as a Unique Index, meaning that it can guarantee that the values in this field won’t be duplicated and should be kept sorted for faster queries. (Later we’ll talk a little more about optimizing queries by adding additional table indices.)

The Autoinc checkbox tells SQLite how to handle the automatic creation of primary key values. Without autoinc being checked, when a new row is added SQLite sets the primary key to one greater than the current highest primary key. With the box checked, SQLite sets the primary key to one greater than the highest primary key that the table has every had. (Which it keeps track of in its own table called sqlite_sequence). How you set this box will depend on how you want to handle deleted records.

For the Ingredients table, it is much the same:

Notice that we do NOT mark the Recipe_ID field of the Ingredients table as a primary key. It is the primary key of the Recipes table, not of this table. (In this table some people would call the Recipe_ID field the foreign key).

The last thing that we want to do regarding our database schema is to create an index on the Recipe_ID field of the Ingredients table. Since most of our queries that involve this table will involve looking up a specific value in the Recipe_ID field, it will speed things up to have an index on this field. (Note: You really won’t notice a significant speed increase unless your Ingredients table has a lot of records, but since it is a good design principle, we’re going to do it anyway.)

Finally you need to populate the table with some data. You can do that using the SQLite Manager by selecting the table and then clicking the “Add new Record” button, or by selecting the “Execute SQL” tab and using several Insert statements.

For example to insert this data into my Recipes table:

Recipe_ID	Name	Description
1	Omelet	A delicious and eggy breakfast.
2	Grilled Cheese Sandwich	A delicious and cheese filled lunch.
3	Pizza	A classic dinner from the old world.

I could use these three insert statements:

INSERT into Recipes(Name, Description) VALUES(’Omelet’, ‘A delicious and eggy breakfast.’);

INSERT into Recipes(Name, Description) VALUES(’Grilled Cheese Sandwich’, ‘A delicious and cheese filled lunch.’);

INSERT into Recipes(Name, Description) VALUES(’Pizza’, ‘A classic dinner from the old world.’);

Notice that I did not insert the values for the Recipe_ID field. As I mentioned above, since it is the primary key the database calculates those values automatically.

Next comes the Ingredients table:

Ingredient_ID	Recipe_ID	Description
1	1	Eggs
2	1	Water
3	1	Salt
4	2	Bread
5	2	Cheese
6	2	Butter
7	3	Pizza Dough
8	3	Pizza Sauce
9	3	Cheese
10	3	Toppings

Which I could use the following statements for:

INSERT into Ingredients(Recipe_ID, Description) VALUES(1, ‘Eggs’);

INSERT into Ingredients(Recipe_ID, Description) VALUES(1, ‘Water’);

INSERT into Ingredients(Recipe_ID, Description) VALUES(1, ‘Salt’);

INSERT into Ingredients(Recipe_ID, Description) VALUES(2, ‘Bread’);

…

INSERT into Ingredients(Recipe_ID, Description) VALUES(3, ‘Toppings’);

Again notice that I did not specify the values for the table’s primary key (Ingredient_ID), but I did specify the foreign key values (Recipe_ID).

Step 3: Add the Database File to Your XCode Project

To do this, just right click on the Resources folder and select “Add->Existing Files…” and then select the database file that you created.

XCode should automatically add the file that you select to the “Copy Bundle Resources” build phase of your project target. (Meaning that when the program is compiled, your database file is automatically stored in the application bundle’s resource folder so that you can access it from your application.)

Update: Jonathan Wight suggested that instead of embedding the SQLite db file directly into the XCode project, it is better to embed the SQL source file into the project and then setup a compile rule in XCode to generate the db file and embed it into the bundle at compile time. As he points out this has a particular advantage related to source code control. He provides an example of how to do this here.

Step 4: Link to the SQLite Library

Finally you are ready to link to the library that contains all of the SQLite functions. To link to that library, from your XCode project right click the frameworks folder and select “Add->Existing Frameworks…”.

Next, navigate to the your iPhoneSDK folder and select the usr/lib/libsqlite3.0.dylib file. (Don’t be confused by the other libsqlite*.lib files in that folder, they are all just aliases to this one.)

You are now ready to start writing some SQLite code. (Again see the SQLiteBooks sample code for some tips on doing that.)

Update: Jonathan Wight also suggested that it is better to use the other linker flags setting in the the Build tab of the Project settings to link to the SQLite library instead of using the framework method. You can do this by adding the -lsqlite3 flag to that field as shown here:

This method has the advantage of linking to the correct library no matter what platform you are targeting.

SQLite on the iPhone Nuances

1. SQLite on the actual iPhone is much slower for some things than on the simulator. In particular the same queries that run in the blink of an eye on the simulator take several seconds to run on the actual device.
2. If you need to write to your database, make sure you make a copy of it in a location that you can write to. See the SQLiteBooks sample code for an example of how to do this.
3. Be aware that SQLite extensions such as Full Text Search don’t appear to be compiled into the iPhone SQLite libraries.
4. Plan for the future! If you plan on adding a feature that relies on a certain table or field in the database make that part of your database design now. This will save you the trouble of having to write all the necessary SQL commands for versioning your database later when you release an application update.