Not able to query my sqlite database - ios

Question

Below is my code, I'm attempting to retrieve data from an sqlite database with airport city names query from a user entered text field and retrieve the ICAO identifier to be presented in a label. It seems the db is loading but it will not query when I select the IBAction button. I think there might be something wrong with my query statement or my database, although I can't list that on here. Any Help would be greatly appreciated.
The Last error I received is: database3[30351:c07] -[ViewController searchICAO:] 1st SQL error 'library routine called out of sequence' (21)
-(NSString*)filePath {
NSArray*paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
return [[paths objectAtIndex:0]stringByAppendingPathComponent:#"mydatabase.sqlite"];
}
//open database
- (void)viewDidLoad{
[self openDB];
}
-(void)openDB {
if(sqlite3_open([[self filePath]UTF8String], &airportDB) !=SQLITE_OK) {
sqlite3_close(airportDB);
NSAssert(0, #"Databese failed to open");
status.text = #"Database Failed to Open";
}
else if (sqlite3_open([[self filePath]UTF8String], &airportDB) ==SQLITE_OK) {//this line not really needed but was trying everything
NSLog(#"database opened"); //test
status.text = #"Database Opened"; //test
}
}
- (IBAction)searchICAO:(id)sender
{
//[self.delegate detailViewControllerDidFinish:self]; //for later use
//Get airport name from the text field user enters
NSString*sql = [NSString stringWithFormat:#"SELECT * FROM airports WHERE city=\"%#\"", [searchDB text]];
const char *query_stmt = [sql UTF8String];
sqlite3_stmt *statement;
NSLog(#"%s 1st SQL error '%s' (%1d)", __FUNCTION__, sqlite3_errmsg(airportDB), sqlite3_errcode(airportDB)); //Error Test
This is where I seem to be having problems at...
if (sqlite3_prepare_v2(airportDB, query_stmt, -1, &statement, NULL)==SQLITE_OK) {// Problem is from here, can't get past this point
NSLog(#"%s 2nd SQL error '%s' (%1d)", __FUNCTION__, sqlite3_errmsg(airportDB), sqlite3_errcode(airportDB)); //Error Test
if (sqlite3_step(statement)==SQLITE_ROW) {
status.text = #""; //Clear the status line
NSString *returnICAO = [[NSString alloc] initWithUTF8String:(const char *) sqlite3_column_text(statement, 1)];
status.text = returnICAO; //Insert Airport ICAO letters from the database table
}
sqlite3_finalize(statement);
[super viewDidLoad];
}
sqlite3_close(airportDB);
}

Answer 1

I am not seeing exactly what is going wrong, but I would offer that, unless you have a specific objective that cannot be met by using third-party code, you should consider using FMDB https://github.com/ccgus/fmdb - assuming that you need to go directly to SQLite. I have used it quite a bit and had good success with it.
It's a little strange to be "closing" the DB and calling [super viewDidLoad] from searchICAO:. Was this deliberate? It seems like this might be the source of your problem? On the second query, the DB will be closed?