Ticket #33501: 33501.patch

src/wp-includes/wp-db.php

@@ -2401 +2401 @@
                 }
 
                 // Skip this entirely if this isn't a MySQL database.
-                if ( false === $this->is_mysql ) {
+                if ( false === $this->is_mysql || empty( $this->is_mysql ) ) {
                         return false;
                 }
 
@@ -2450 +2450 @@
                 $columnkey = strtolower( $column );
 
                 // Skip this entirely if this isn't a MySQL database.
-                if ( false === $this->is_mysql ) {
+                if ( false === $this->is_mysql || empty( $this->is_mysql ) ) {
                         return false;
                 }