diff --git a/htdocs/install/mysql/migration/3.0.0-3.1.0.sql b/htdocs/install/mysql/migration/3.0.0-3.1.0.sql
index 1de2e5617aa..931a1e1c12f 100755
--- a/htdocs/install/mysql/migration/3.0.0-3.1.0.sql
+++ b/htdocs/install/mysql/migration/3.0.0-3.1.0.sql
@@ -484,4 +484,7 @@ ALTER TABLE llx_don ADD   phone           varchar(24) after email;
 ALTER TABLE llx_user ADD civilite varchar(6) after entity;
 
 ALTER TABLE llx_element_element MODIFY sourcetype varchar(32) NOT NULL;
-ALTER TABLE llx_element_element MODIFY targettype varchar(32) NOT NULL;
\ No newline at end of file
+ALTER TABLE llx_element_element MODIFY targettype varchar(32) NOT NULL;
+
+ALTER TABLE llx_societe_prices MODIFY tms timestamp NULL;
+-- ALTER TABLE llx_societe_prices ALTER COLUMN tms DROP NOT NULL;