how do I check if this value is lower than previous?

ejwf

I have a databse that stores user input information.
I want to check that the information they are adding is of a value that is greater than the previous months information.
I can get so that the previous months info is displayed within the user input form as a visual check. But I want a check within the code so that if the user carries on and inputs a lower value it throws up an error message.........

code I have so far (but isn't doing what I want)

echo' <form action="process.php" method="POST" > 
<table align="centre" cellspacing="0" cellpadding="0"> 
<tr valign="top">
<td width="5"></td>
<td width="5"></td>
<td align="right" width="50"><b>Serial</b></td>
<td align="left" width="200"><b> &nbsp;&nbsp/ Known As</b></td> 
<td align="right" width="20"><b>Code</b></td> 
<td align="right" width="20"></td>
<td align="right" width="200">Previous Months B&nbsp;&nbsp</td>
<td align="left" width="200"><b>This Months B</b></td> 
<td align="right" width="200">Previous Months C &nbsp;&nbsp</td>
<td align="left" width="200"><b>This Months C</b></td> 
</tr >';

while ($row2 = mysql_fetch_array($result2,MYSQL_NUM)) 
{ 
$query= "SELECT (MRef) AS MRef, Max(B) As LastResultB, Max(C) As LastResultC 
FROM tblResults 
WHERE MRef = '".$row2[2]."' 
AND CRef = $CRef 
GROUP BY MRef, CRef";
$result3 = mysql_query($query) or die (mysql_error());
$row3 = mysql_fetch_array($result3);

echo "<td width=\"5\" align=\"left\"><input type=\"hidden\" name=\"List\" value=\"{$row2[3]}\"></td>
<td width=\"5\" align=\"left\"><input type=\"hidden\" name=\"SRef\" value=\"$SRef\"></td>"; 

echo "<td width=\"50\" align=\"left\"> {$row2[0]}</td> 
<td width=\"200\" align=\"left\">  &nbsp;&nbsp/ {$row2[1]}</td> 
<td width=\"20\" align=\"right\"> {$row2[2]}</td>
<td width=\"20\" align=\"left\"> {$row2[4]} <input type=\"text\" name=\"MId[]\" size=\"3\"></td>
<td width=\"200\" align=\"right\"> $row3[1] &nbsp;&nbsp</td>
<td width=\"200\" align=\"left\"> {$row2[5]} <input type=\"text\" name=\"B[]\"> </td> 
<td width=\"200\" align=\"right\"> $row3[2] &nbsp;&nbsp</td>
<td width=\"200\" align=\"left\"> {$row2[6]} <input type=\"text\" name=\"C[]\"></td>";

}  // close while loop 

} //close main if

// this is the part where I am trying to add the clause
if ('B' < '$row3[1]')
{
echo "Please note that the information you have input for <b>'Name'</b> is lower than the previous months. <br>
Please go back and correct this reading. Thank You.";
}
else if ('C' < '$row3[2]')
{
echo "Please note that the information you have input for <b>'Name'</b> is lower than the previous months. <br>
Please go back and correct this reading. Thank You.";
}
else 
{
echo '</table>';
echo "<br><p align=\"center\"><input type=\"submit\" name=\"submit\" value=\"Submit\"> "; 
echo '</form>';
}

Installer

You can't do this with PHP without submitting the form and loading a script that processes the input. To deal with it as it's entered you'll need to use client-side scripting with, for example, javascript.

ejwf

Seeing as I wouldn't know where to start with this in javascript and as I already have a code to process the form I am going down that route ........ but needless to say can't get it to work.....

code I have in the file to process the form I am trying the following to check is the value is higher than the previous months(this is amongst other bits of code that create other error messages and the instruction to Insert the info into the database).
Any Ideas where I am going wrong....... thanks

if (is_array($_POST['MId']) && count ($_POST['MId']) >0)
{
$arr_size = count($_POST['MId']);
  for ($i=0; $i< $arr_size; $i++)  

  	{  

	// find last months info
	$query= "SELECT (MRef) AS MRef, Max(B) As LastResultB, 
	Max(C) As LastResultC, (Name) As Name FROM tblResults, tblM 
	WHERE tblResults.MRef = '".$_POST['MId']."'
	AND tblM.MId = tblResults.MRef
	AND tblResults.CRef = '".$row101[1]."'
	AND tblResults.SRef = '".$row101[2]."'
	AND tblResults.CoRef = '".$row101[0]."'
	GROUP BY MRef, tblResults.CRef, tblResults.SRef, tblResults.CoRef";
	$result3 = mysql_query($query) or die (mysql_error());
	$row3 = mysql_fetch_array($result3);

if (($_POST['B'][i]) < ($row3[1]))
   {   $count_check = sizeof($i); 

		if ($count_check > 0) 
		{
			echo "<br><br>" . 
             "<font face=\"Arial, Helvetica, sans-serif\">" . 
             "Sorry, it appears that the information for  <b>'$row3[3]'</b> " . 
             "is lower than that entered last month.<br>Please kindly return to the " . 
             "input form, and re-enter this information .  " . 
             "<br>Thank you" . 
             "</font>"; 
	   }
	}

Installer

First of all, "$POST['mid']" is a text input, and as such will be a string scalar, not an array; your script won't get past the first line. Even if by a miracle it did, "count(POST['mid'])" will be 1, and your loop will execute only once. But that's probably not completely a bad thing, since you have your query inside the loop. It would be called every time through.

You have "if (($POST['B']) < ($row3[1]))". I'm not sure, but I don't think the size of a non-existent array relates to anything here--"$POST['B']", like "$_POST['mid']", isn't itself an array. And "$count_check = sizeof($i)": that also will always return 1, because it's the element count of a scalar...which is in turn the element count of a scalar. As for "if ($count_check > 0)", well, of course it's going to always be true.

I don't know what you expect your query to return, what "$row101" is, or what kind of data you expect to be posted, or I'd write a little code to get you started. So my advice is to start over. 🙂