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This query always returns "1", Not quite sure whats wrong?
Thanks
DS

<pre lang="cs">if (mysql_real_connect(conn,"urlock.db.5513143.hostedresource.com","VendorCheck","Reader1234","urlock",0,NULL,0) !=0)
     {
    legal = mysql_query(conn, "SELECT COUNT(*) FROM tblURL WHERE IP = '192.168.1.1'");
        if( legal != 0 )
        {
            printf(mysql_error(conn)); return 99;
        }
        result = mysql_store_result(conn);
        printf("Legal: %d\n", mysql_num_rows(result));
        mysql_free_result(result);
        mysql_close(conn);

Posted

If I'm interpreting the code correctly, then you're polling the resultset for the number of rows it has, not the actual returned value. The number of rows will always be 1, since a count query always returns one result. In other words, you're looking at the number of results, not the result itself. At least, that's what it looks like :)

Code in question:
printf("Legal: %d\n", mysql_num_rows(result));
 
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v2
Comments
Member 7766180 10-May-11 15:29pm    
Spot on! How do I get it to return either a "1" if it does match or "0" if it doesn't?
Thanks
DS
Member 7766180 10-May-11 15:36pm    
I want it to check if there is a match on the IP address. If there is a match then it's "1" No match "0"
R. Hoffmann 10-May-11 15:43pm    
Sorry, I'm not familiar with MySQL at all, but this page may be of help: http://php.net/manual/en/function.mysql-query.php.

Seems like they
1. execute the function using mysql_query, which returns a resultset of some sort,
2. call mysql_fetch_assoc on the resultset to obtain the next row from it, which is returned,
3. and lastly, refer to a specific value in the row by using an indexer in the form of the field name to be returned.
OriginalGriff 10-May-11 15:37pm    
Good catch!
R. Hoffmann 10-May-11 15:47pm    
Thanks :)
I wonder how many times this has to be explained to you in this and your previous question[^] before you understand? The SELECT command does not return a value giving the answer to your query, it returns a value telling you how many database rows it found. You then need to interpret the contents of those rows for the information you are looking for.

Posting comments like C++ can't return integers!???! Oh boy. merely shows how far away you are from understanding any of the responses that have been posted, and possibly both C++ and SQL.
 
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Comments
Member 7766180 10-May-11 16:36pm    
Ok, "NOW", I understand! The SELECT tells me how many rows I have!
OK, I have (3) rows in the database at this point. I am not even getting that. I took away the criteria and still not getting the correct answer! It only needs to be explained once "clearly" as you just did!
Kim Togo 11-May-11 2:52am    
Correct Richard
Perhaps you only have one matching record in your database?
 
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Comments
Member 7766180 10-May-11 14:52pm    
DUH? I've been at this too long! lol! Your right, I do only have one matching record. However: when I change the IP to one that isn't in the db, it still returns "1".
Thanks
DS
Member 7766180 10-May-11 15:14pm    
In think it might be in the logic?
<pre>#include "stdafx.h"
#include <stdio.h>
#include <iostream>
#include <string>
#include <conio.h>
#include <fstream>
#include <windows.h>
#include <winsock.h>
#include <c:\\mysql\\include\\mysql.h>

using namespace std;

int main()
{
MYSQL_RES *result;
MYSQL* conn;
int legal;

conn = mysql_init(NULL);
if (mysql_real_connect(conn,"urlock.db.5513143.hostedresource.com","VendorCheck","Reader1234","urlock",0,NULL,0) !=0)
{
legal = mysql_query(conn, "SELECT COUNT(*) FROM tblURL WHERE IP = '192.168.1.99'");
if( legal != 0 )
{
result = mysql_store_result(conn);
printf(mysql_error(conn)); return 0;
}
else if( legal != 1 )
{
result = mysql_store_result(conn);
printf("Legal: %d\n", mysql_num_rows(result));
}
mysql_free_result(result);
mysql_close(conn);
}
else
{
cout << "Conn Failed!" <<endl;
}
system("PAUSE"); /*Remove After Testing*/
return 0;
}
</pre>
Member 7766180 10-May-11 15:17pm    
Don't know what happened to the #includes!
Graham Breach 10-May-11 15:18pm    
If the count is 0, you'll still get one row containing the value 0.
OriginalGriff 10-May-11 15:28pm    
R Hoffman, and Graham are right: your query will return a row containing the count only. Unfortunately, there doesn't appear to be any way to directly call scalar functions as you can with .NET so you will have to retrieve the result yourself!

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