Close #3194
diff --git a/system/database/DB_query_builder.php b/system/database/DB_query_builder.php
index 30882fa..2096ffd 100644
--- a/system/database/DB_query_builder.php
+++ b/system/database/DB_query_builder.php
@@ -661,6 +661,10 @@
// value appears not to have been set, assign the test to IS NULL
$k .= ' IS NULL';
}
+ elseif (preg_match('/\s*(!?=|<>)\s*$/i', $k, $match, PREG_OFFSET_CAPTURE))
+ {
+ $k = substr($k, 0, $match[0][1]).($match[1][0] === '=' ? ' IS NULL' : ' IS NOT NULL');
+ }
$this->{$qb_key}[] = array('condition' => $prefix.$k.$v, 'escape' => $escape);
if ($this->qb_caching === TRUE)