Getting error while trying to make writeable copy of sqlite - objective-c

Question

I have a copy of my db in Supporting Files folder. I need update a couple of tables and I am trying to use method to make writeable copy of db.
- (void) createEditableDatabase
{
BOOL success;
NSFileManager *fileManager = [NSFileManager defaultManager];
NSError *error;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES);
NSString *documentsDir = [paths objectAtIndex:0];
NSString *writableDB = [documentsDir stringByAppendingPathComponent:#"yc_ch.db"];
success = [fileManager fileExistsAtPath:writableDB];
NSString *defaultPath = [[[NSBundle mainBundle]resourcePath]stringByAppendingPathComponent:#"yc_ch.db"];
success = [fileManager copyItemAtPath:defaultPath toPath:writableDB error:&error];
if (!success)
{
NSAssert1(0, #"Failed to create writable database file:'%#'.", [error localizedDescription]);
}
}
I have created (typed, physically) the 'Documents' folder in the root. At moment hierarchy of docs looks like this:
When I run my app. I am getting NSAssert1(0, #"Failed to create writable database file:'%#'.", [error localizedDescription]);.
What's wrong with it?

Answer 1

You copy the file even if the file already exists in the Document, I think NSFileManager copyFileAtPath: will return NO if file already exists at destination, hence failing your check and raising your NSAssert
success = [fileManager fileExistsAtPath:writableDB];
if (success)
{
return;
}
So the file isn't copied over if it already exists in your document. If that's what causing the error, can you actually post the assertion, [error localizedDescription] will at least tell you what is wrong with it at the moment.
Edit:
- (void) createEditableDatabase
{
BOOL success;
NSFileManager *fileManager = [NSFileManager defaultManager];
NSError *error;
NSString *writableDB = [[NSHomeDirectory() stringByAppendingPathComponent:#"Documents"] stringByAppendingPathComponent:#"yc_ch.db"];
NSLog(#"Document path = %#", writableDB);
success = [fileManager fileExistsAtPath:writableDB];
if (success)
{
return;
}
NSString *defaultPath = [[NSBundle mainBundle] pathForResource:#"yc_ch" ofType:#"db"];
NSLog(#"defaultPath = %#", defaultPath);
error = nil;
success = [fileManager copyItemAtPath:defaultPath toPath:writableDB error:&error];
if (!success)
{
NSAssert1(0, #"Failed to create writable database file:%#", [error localizedDescription]);
}
if (error)
{
NSLog(#"error = %#", [error localizedDescription]);
}
}