diff --git a/classes/Schema_version.php b/classes/Schema_version.php
index ae6e97980f..fe89bb88fb 100644
--- a/classes/Schema_version.php
+++ b/classes/Schema_version.php
@@ -27,7 +27,7 @@ class Schema_version extends Managed_DataObject
 
     public $__table = 'schema_version';      // table name
     public $table_name;                      // varchar(64)  primary_key not_null
-    public $checksum;                        // varchar(64)  not_null
+    public $checksum;                        // varchar(128) not_null
     public $modified;                        // timestamp()  not_null default_CURRENT_TIMESTAMP
 
     /* the code above is auto generated do not remove the tag below */
@@ -39,7 +39,7 @@ class Schema_version extends Managed_DataObject
             'description' => 'To avoid checking database structure all the time, we store a checksum of the expected schema info for each table here. If it has not changed since the last time we checked the table, we can leave it as is.',
             'fields' => array(
                 'table_name' => array('type' => 'varchar', 'length' => '64', 'not null' => true, 'description' => 'Table name'),
-                'checksum' => array('type' => 'varchar', 'length' => '64', 'not null' => true, 'description' => 'Checksum of schema array; a mismatch indicates we should check the table more thoroughly.'),
+                'checksum' => array('type' => 'varchar', 'length' => '128', 'not null' => true, 'description' => 'Checksum of schema array; a mismatch indicates we should check the table more thoroughly.'),
                 'modified' => array('type' => 'timestamp', 'not null' => true, 'description' => 'date this record was modified'),
             ),
             'primary key' => array('table_name'),
diff --git a/lib/database/schemaupdater.php b/lib/database/schemaupdater.php
index 7b2ea4fe04..a647002289 100644
--- a/lib/database/schemaupdater.php
+++ b/lib/database/schemaupdater.php
@@ -82,7 +82,7 @@ class SchemaUpdater
     public function checksum(array $def)
     {
         $flat = serialize($def);
-        return sha1($flat);
+        return hash('sha3-256', $flat);
     }
 
     /**