diff --git a/mod/glossary/editcategories.php b/mod/glossary/editcategories.php
index 2e93b211b19..c83192d1802 100644
--- a/mod/glossary/editcategories.php
+++ b/mod/glossary/editcategories.php
@@ -158,8 +158,7 @@ if ( $hook >0 ) {
 
 } elseif ( $action == "add" ) {
     if ( $confirm ) {
-        $ILIKE = $DB->sql_ilike();
-        $dupcategory = $DB->get_records_sql("SELECT * FROM {glossary_categories} WHERE name $ILIKE ? AND glossaryid=?", array($name, $glossary->id));
+        $dupcategory = $DB->get_records_sql("SELECT * FROM {glossary_categories} WHERE ".$DB->sql_like('name','?', false)." AND glossaryid=?", array($name, $glossary->id));
         if ( $dupcategory ) {
         echo "<h3 class=\"main\">" . get_string("add"). " " . get_string("category","glossary"). "</h3>";
 
diff --git a/mod/glossary/lib.php b/mod/glossary/lib.php
index e79d636b8cb..b04b5c5ef8c 100644
--- a/mod/glossary/lib.php
+++ b/mod/glossary/lib.php
@@ -1200,7 +1200,6 @@ function glossary_search($course, $searchterms, $extended = 0, $glossary = NULL)
         $REGEXP    = $DB->sql_regex(true);
         $NOTREGEXP = $DB->sql_regex(false);
     }
-    $LIKE = $DB->sql_ilike(); // case-insensitive
 
     $searchcond = array();
     $params     = array();
@@ -1212,14 +1211,14 @@ function glossary_search($course, $searchterms, $extended = 0, $glossary = NULL)
     foreach ($searchterms as $searchterm) {
         $i++;
 
-        $NOT = ''; /// Initially we aren't going to perform NOT LIKE searches, only MSSQL and Oracle
+        $NOT = false; /// Initially we aren't going to perform NOT LIKE searches, only MSSQL and Oracle
                    /// will use it to simulate the "-" operator with LIKE clause
 
     /// Under Oracle and MSSQL, trim the + and - operators and perform
     /// simpler LIKE (or NOT LIKE) queries
         if (!$DB->sql_regex_supported()) {
             if (substr($searchterm, 0, 1) == '-') {
-                $NOT = ' NOT ';
+                $NOT = true;
             }
             $searchterm = trim($searchterm, '+-');
         }
@@ -1239,7 +1238,11 @@ function glossary_search($course, $searchterms, $extended = 0, $glossary = NULL)
             $params['ss'.$i] = "(^|[^a-zA-Z0-9])$searchterm([^a-zA-Z0-9]|$)";
 
         } else {
-            $searchcond[] = "$concat $NOT $LIKE :ss$i";
+            if ($NOT) {
+                $searchcond[] = "$concat NOT LIKE :ss$i"; //TODO: MDL-24080
+            } else {
+                $searchcond[] = $DB->sql_like($concat, ":ss$i", false);
+            }
             $params['ss'.$i] = "%$searchterm%";
         }
     }
diff --git a/mod/glossary/sql.php b/mod/glossary/sql.php
index 9888f2730c4..6349de2e1db 100644
--- a/mod/glossary/sql.php
+++ b/mod/glossary/sql.php
@@ -145,7 +145,6 @@
                 $REGEXP    = $DB->sql_regex(true);
                 $NOTREGEXP = $DB->sql_regex(false);
             }
-            $LIKE = $DB->sql_ilike(); // case-insensitive
 
             $searchcond = array();
             $alcond     = array();
@@ -159,14 +158,14 @@
             foreach ($searchterms as $searchterm) {
                 $i++;
 
-                $NOT = ''; /// Initially we aren't going to perform NOT LIKE searches, only MSSQL and Oracle
+                $NOT = false; /// Initially we aren't going to perform NOT LIKE searches, only MSSQL and Oracle
                            /// will use it to simulate the "-" operator with LIKE clause
 
             /// Under Oracle and MSSQL, trim the + and - operators and perform
             /// simpler LIKE (or NOT LIKE) queries
                 if (!$DB->sql_regex_supported()) {
                     if (substr($searchterm, 0, 1) == '-') {
-                        $NOT = ' NOT ';
+                        $NOT = true;
                     }
                     $searchterm = trim($searchterm, '+-');
                 }
@@ -193,13 +192,17 @@
                     if ($textlib->strlen($searchterm) < 2) {
                         continue;
                     }
-                    $searchcond[] = "$concat $NOT $LIKE :ss$i";
+                    if ($NOT) {
+                        $searchcond[] = "$concat NOT LIKE :ss$i"; //TODO: MDL-24080
+                    } else {
+                        $searchcond[] = $DB->sql_like($concat, ":ss$i", false);
+                    }
                     $params['ss'.$i] = "%$searchterm%";
                 }
             }
 
             if (empty($searchcond)) {
-                $where = " 1=2 "; // no search result
+                $where = "AND 1=2 "; // no search result
 
             } else {
                 $searchcond = implode(" AND ", $searchcond);