diff --git a/system/database.php b/system/database.php
index cf59baf..586fc75 100644
--- a/system/database.php
+++ b/system/database.php
@@ -382,7 +382,7 @@ if(!check_function_exists("get_bind_to_sql_select")) {
                 // use simple distance
                 if(!array_key_empty("simple_distance", $v)) {
                     if(check_array_length($v['simple_distance'], 2) == 0) {
-                        $a = $v['simple_distance'][1]; // percentage (range 0 to 1)
+                        $a = floatval($v['simple_distance'][1]); // percentage (range 0 to 1)
                         $b = $v['simple_distance'][0]; // field or number
                         $s1a[$k] = sprintf("abs(1.0 - (abs(%s - %s) / %s))", $b, $a, $a);
                     }