login page problem in iphone - iphone

Question

I'm getting the same problem, one of stackoverflow which is:
if(sqlite3_open([dbPath UTF8String], &database) == SQLITE_OK)
{
//const char *sql ="select Username#'%#',Password#'%#' from userinformation";
NSString *sql = [[NSString alloc] initWithFormat:#"select * from UserInformation where UserName='%#' and Password='%#' ",Username.text,Password.text];
sqlite3_stmt *selectSatement;
// Here i am getting the problem.Im not sure why sqlite3_prepare_v2 ins't meeting SQLITE_OK
if( sqlite3_prepare_v2(database, [sql UTF8String], -1, &selectSatement, NULL) == SQLITE_OK)
{
//-------------------------------------
//Loop all the
NSString *user1 = [NSString stringWithUTF8String:(char *)sqlite3_column_text(selectSatement, 0)];
NSLog(#"%#",user1);
}
}
Any help with this is greatly appreciated.

Answer 1

First of all: if you open the database, you should also close it by using sqlite3_close(database)
I wrote in the code below an assert-statement, which will tell you, if something is wronmg with your query. Further on you might get an error, if your password or username is for some reason "nil", that's why I adapted the way you set the username and password a bit. If the value does not exist, its "0"
if(sqlite3_open([dbPath UTF8String], &database) == SQLITE_OK)
{
char *errorMsg;
NSString *sql = [[NSString alloc] initWithFormat: #"SELECT * FROM UserInformation WHERE UserName=\"%#\" and Password =\"%#\"", Username.text, Password.text];
if (sqlite3_exec (database, [sql UTF8String], NULL, NULL, &errorMsg) != SQLITE_OK)
{
sqlite3_close(database);
NSAssert1(0, #"Error selecting data: %s", sqlite3_errmsg(database));
}
else
{
NSString *user1 = [NSString stringWithUTF8String:((char *)sqlite3_column_text(compiledStatement, 0) ? (char *)sqlite3_column_text(compiledStatement, 0) : (char *)"0")];
NSString *password1 = [NSString stringWithUTF8String:((char *)sqlite3_column_text(compiledStatement, 1) ? (char *)sqlite3_column_text(compiledStatement, 1) : (char *)"0")];
NSLog(#"%#: %#",user1,password1);
}
[sql release];
}
sqlite3_close(database);
What you should also keep in mind is, that the database should exist at the intended path, by calling for example the following method
-(void) checkAndCreateDatabase
{
NSFileManager *fileManager = [NSFileManager defaultManager];
if([fileManager fileExistsAtPath:dbPath]) return;
NSString *databasePathFromApp = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:databaseName];
[fileManager copyItemAtPath:databasePathFromApp toPath:databasePath error:nil];
[fileManager release];
}

Answer 2

Check the query itself, print it in log and check it by copying it from log and executing directly in the database.