difficluty with a if statement

[spearchilduser]

$sql = "SELECT * FROM studproj WHERE Enrolement_Number = students.'$username'";
$results = mysql_query($sql);

//echo $results;

//echo $sql;

if(mysql_num_rows($result) == 0) 
{ 
echo "You already have a project chosen you cannot choose another but you can see your selection on the main page!"; 
exit;
} 
else 
{ 
echo " Please continue and choose your Project";
} 

?>

 

this is the code however i dont know what to put where ==0 is so that it says if there is a row that matches then choose an error message any help ?

[spearchilduser]

the result btw

[samshel]

not sure if i understand...but try this.

if(mysql_num_rows($result) > 0) 

[AyKay47]

in the mysql_num_rows call, the variable should be $results, not $result.

what exactly are you asking?

[spearchilduser]

ive changed it a little bit

 

$sql = "SELECT * FROM studproj WHERE Enrolement_Number ='$username'";
$result = mysql_query($sql);

//echo $result;

//echo $sql;

if(!$result) {
  // problem with query
echo "query is wrong";
}
elseif (mysql_num_rows($result)) {
echo " Please continue and choose your Project";
}
else 
{
  echo "You already have a project chosen you cannot choose another but you can see your selection on the main page!";

}
?>

 

but it always still just returns as if the query  is true

[kicken]

So instead of checking for zero rows, you want to check for one or more rows?  How about using >= 1 then.

 

if(mysql_num_rows($results) >= 1) 

 

[spearchilduser]

ive done these however it always shows the result as if the user has a entry in the databse when ive emptied the database so it should be telling them to choose a project

 

 

?php 

$username = $_SESSION['valid_user'];

ECHO $username;



$sql = "SELECT * FROM studproj WHERE Enrolement_Number ='$username'";
$result = mysql_query($sql);

//echo $result;

//echo $sql;

if(!$result) {
  // problem with query
echo "query is wrong";
}
elseif (mysql_num_rows($result)>= 1) {
echo " Please continue and choose your Project";
}
else 
{
  echo "You already have a project chosen you cannot choose another but you can see your selection on the main page!";

}
?>

[samshel]

check if your query is failing:

 

$result = mysql_query($sql) or die(mysql_error());

[scootstah]

What does echo mysql_num_rows($result); give you?

[spearchilduser]

THE ECHO dispalys the username and 0

[kicken]

When you change your condition, you also changed your echo's so they no longer match up with what you checking.  You need to make sure what you put inside your if statement's code body matches what you want to do under that condition.

 

if (mysql_num_rows($results) >= 1){
  echo 'You already have a project';
}
else {
  echo 'You must choose a project.';
}

 

[spearchilduser]

even with the change to make sure the changes have been made it still always seems to choose the else {} option

[AyKay47]

then there aren't any rows being grabbed from your query.

Have you debugged your query?

[spearchilduser]

yes ive debugged it:

 

 

echo mysql_num_rows($result);  = dan0

echo $sql =  shows the statment and dan where the $username is

echo $result = resource4#

 

[AyKay47]

echo mysql_num_rows($result);  = 0

this means that there are 0 results being returned.

Something is not right in the SQL if you are expecting results.

[spearchilduser]

Aww ive found the problem im asking it to match the enrolement number with the users username when it needs to

 

look into the s6tudents table and match the username with the enrolement number that has that username

 

would that be a join statement ? ive never had to do this before so im really not sure

[AyKay47]

would that be a join statement ?

 

yes, refer to the join documentation for correct syntax

[spearchilduser]

im getting rrally confused by the joining document

woudl i be able to take a shortcut and do something like :

 

$sql1 = "Select Enrolement_Number FROM students WHERE First_Name ='$username'"; 
$result1 = mysql_query($sql1) or die(mysql_error());
echo $result1;
$sql = ("SELECT * FROM studproj WHERE Enrolement_Number  = '$result1'") or die (mysql_error());
$result = mysql_query($sql) or die(mysql_error());

echo mysql_num_rows($result); 

[spearchilduser]

ive had one try of it

 

so what im tryign to say is select all from the studprojc table if the enrolement number matches a field with the username init  from the students table

$sql1 = ("Select * FROM studproj INNER JOIN students ON students.First_Name = Students.'$username'"); 

[spearchilduser]

i finally got the join statment to work wether its the best way to do it im not sure but it works not im havign difficulties taking the filed names and storing them into attributes to disply information from them:

 

$sql = ("Select project.Module_Code,project.Title,project.First_Supervisor,project.Level,project.Description,studproj.Module_Code FROM studproj INNER JOIN project ON  studproj.Module_Code=project.Module_Code "); 
$result = mysql_query($sql) or die(mysql_error());

 

f (mysql_num_rows($result1)==1)
{
echo 'You already have a project';

while ($row = mysql_fetch_row($result)) 
{
$enrolementnumber = $row['Enrolement_Number'];
$Modulecode = $row['Module_Code'];
$Title = $row['Title'];               
$First_Supervisor = $row['First_Supervisor'];                
$Level = $row['Level'];
$Description = $row['Description'];
echo '<table border = "2">

<tr>
<td>Module Code </td><td><input readonly type= "text" name="Module_Code1"></td>
<td>Title </td><td><input readonly type= "text" name="Title1" ></td>
<td>First Supervisor </td><td><input readonly type= "text" name="First_Supervisor1" ></td>
<td>Level </td><td><input readonly type= "text" name="Level1" ></td></tr>
</table>
<table>
<tr>
<td>Description </td><td><input readonly type= "text" size = 200 name="Description1"></td>
</tr>



</table>';

}
}
else {
  echo 'You must choose a project.';


}
?>

 

it wont display the table and i cannot see why it is late so that may be the reason but anyhelp is appricated