Issues using between, min and max - php

Question

I have created a catalog with a block of years search function for characters and the years I've assigned to them. So anything from 1940-1949 would be in the 1940's block of time, and so on. I'm using a href to group these timeframes.
<?php
$sql = "SELECT * FROM catalog";
$displayby = $_GET['displayby'];
$displayvalue = $_GET['displayvalue'];
if($displayby && $displayvalue){
$sql = "SELECT * FROM catalog WHERE $displayby LIKE '$displayvalue'";
}
if($displayby == 'year'){
$min = $_GET['min'];
$max = $_GET['max'];
$sql = "SELECT * FROM catalog WHERE year BETWEEN '$min' AND '$max'";
}
//$result = mysqli_query($con,$sql);
$result = mysqli_query($con,"SELECT * FROM catalog WHERE year BETWEEN '$min' AND '$max'");
while($row = mysqli_fetch_array($result)){
$name = $row['name'];
$filename = $row['filename'];
$cid = $row['cid'];
echo "\n<div class=\"holder\">";
echo "<img src=\"thumbs/$filename\">";
echo "$name<br />\n";
echo "</div>";
}
?>
With this href to only bring up certain characters within those years:
40's Villans<br/>
However they are showing up in the years prior - it might be 1945 as a set date for the character but they only appear in 1930's link.
What am i doing wrong?
Edit : here is the table

Answer 1

BETWEEN ... AND .... can be used for integers and strings. so:
BETWEEN 1 AND 3
Will be true for 1, 2 and 3. But:
BETWEEN 'a' AND 'c'
Will be true for 'a', 'b' and 'c'.
http://dev.mysql.com/doc/refman/5.0/en/comparison-operators.html#operator_between
You've put quotes around your numbers, turning them into strings. So the comparison is done on the characters, not the numbers.
Removing the quotes should make it work.
$result = mysqli_query($con,"SELECT * FROM catalog WHERE year BETWEEN $min AND $max");
But as said by others, there are a lot of other problems with the code. This mistake is a symptom of someone who doesn't really know what they're doing. Why not start at the beginning, and grab a good book. Read it. Do the examples. Experiment. It can take years to become a fluent programmer. (This is meant as an ecouragement, not critizm.)

Answer 2

instead of using between you can also use the following statement for getting the desired data as following
$sql = "SELECT * FROM catalog WHERE year >= '$min' AND year <='$max'";
and in phpmyadmin you can run the query to make sure that you are getting the correct data ,and after that you can check your code where you are displaying it
i hope it help's you..