Use array_keys() rather than array_flip(), which fails for NULL values.

diff --git a/includes/Database.php b/includes/Database.php
index a0e62f9..21256c0 100644 (file)
--- a/includes/Database.php
+++ b/includes/Database.php
@@ -932,7 +932,7 @@ class Database {
                        $rows = array( $rows );
                }
 
-               $sql = "REPLACE INTO $table (" . implode( ',', array_flip( $rows[0] ) ) .') VALUES ';
+               $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) .') VALUES ';
                $first = true;
                foreach ( $rows as $row ) {
                        if ( $first ) {