SQLite Problems when using NSFileManager - objective-c

Question

I am using SQLite and previous answers state that I should use this code:
#import "ViewController.h"
#interface ViewController ()
{
NSMutableArray *arrayOfPerson;
sqlite3 *personDB;
NSString *dbPathString;
}
#end
#implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
arrayOfPerson = [[NSMutableArray alloc]init];
[[self myTableView]setDelegate:self];
[[self myTableView]setDataSource:self];
[self createOrOpenDB];
}
- (void)createOrOpenDB
{
NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *docPath = [path objectAtIndex:0];
dbPathString = [docPath stringByAppendingPathComponent:#"persons.db"];
char *error;
NSFileManager *fileManager = [NSFileManager defaultManager];
BOOL success = [fileManager fileExistsAtPath:dbPathString];
NSLog(#"here 0");
if (!success) {// THIS IS MY CONCERN
const char *dbPath = [dbPathString UTF8String];
NSLog(#"here 1");
//creat db here
NSLog(#"sqlite3 = %d",sqlite3_open(dbPath, &personDB));
NSLog(#"OK= %d", SQLITE_OK);
if (sqlite3_open(dbPath, &personDB)==SQLITE_OK) {
NSLog(#"here 2");
const char *sql_stmt = "CREATE TABLE IF NOT EXISTS PERSONS (ID INTEGER PRIMARY KEY AUTOINCREMENT, NAME TEXT, AGE INTEGER)";
sqlite3_exec(personDB, sql_stmt, NULL, NULL, &error);
sqlite3_close(personDB);
}
}
}
However, when I run this code my app does not gets into this loop:
if(!success) {
....
}
I tried using
if(success) {
....
}
and it works. But I do not think that is correct. Please help me.