Issues when reading from a database in an iPhone app - ios

Question

I am making an iPhone app for a school project that reads and writes to a database. I have managed to get my code to write to it but it won't read. Below is the code I'm using to read:
NSString * paths=[self getWritableDBPath];
const char *dbpath = [paths UTF8String];
sqlite3_stmt *statement;
static sqlite3 *database = nil;
if (sqlite3_open(dbpath, &database) == SQLITE_OK)
{
NSString *querySQL = [NSString stringWithFormat: #"SELECT questionright, totalquestions, FROM results", nil];
const char *query_stmt = [querySQL UTF8String];
if (sqlite3_prepare_v2(database, query_stmt, -1, &statement, NULL) == SQLITE_OK)
{
while(sqlite3_step(statement) == SQLITE_ROW)
{
//code...
}
sqlite3_finalize(statement);
}
sqlite3_close(database);
}
Here is getWritableDBPath:
-(NSString *) getWritableDBPath {
NSString *myDB = #"appData.db";
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory , NSUserDomainMask, YES);
NSString *documentsDir = [paths objectAtIndex:0];
return [documentsDir stringByAppendingPathComponent:myDB];
}
The reason it doesn't work is that the sqlite3_prepare_v2 if statement is never satisfied.
When I write to the database I copy it to documents.
I am quite sure the results table exists as I am able to write to it. Here is the original sql statement:
DROP TABLE IF EXISTS "Questions";
CREATE TABLE "Questions" ("QuestionID" INTEGER PRIMARY KEY NOT NULL , "Question" TEXT, "RightAnswer" TEXT, "WrongAnswer1" TEXT, "WrongAnswer2" TEXT, "Done" BOOL, "Catagory" TEXT, "Audio" INTEGER);
DROP TABLE IF EXISTS "Results";
CREATE TABLE "Results" ("ResultID" INTEGER PRIMARY KEY NOT NULL , "QuestionRight" INTEGER, "TotalQuestions" INTEGER, "Catagory" TEXT);
I did find a similar question on here but didn't think the answers were that relevant to me.
Thanks for your help.

Answer 1

If you want my advice, don't use the sqlite c libraries directly if you don't really need that, you can use FMDB library and get rid of all the c headache
https://github.com/ccgus/fmdb
You can simply do it like this
FMDatabase *db = [FMDatabase databaseWithPath:#"your full db path in documents goes here"];
if (![db open]) {
return;
}
FMResultSet *s = [db executeQuery:#"Your query goes here"];
if ([s next]) {
int totalCount = [s intForColumn:#"totalCount"];
}