-ALTER TABLE kronolith_shares CHANGE share_owner share_owner VARCHAR2(255);
-ALTER TABLE kronolith_shares_users CHANGE user_uid user_uid VARCHAR2(255);
-ALTER TABLE kronolith_shares_groups CHANGE group_uid group_uid VARCHAR2(255);
+ALTER TABLE kronolith_shares MODIFY share_owner VARCHAR2(255);
+ALTER TABLE kronolith_shares_users MODIFY user_uid VARCHAR2(255);
+ALTER TABLE kronolith_shares_groups MODIFY group_uid VARCHAR2(255);
-ALTER TABLE nag_shares CHANGE share_owner share_owner VARCHAR2(255);
-ALTER TABLE nag_shares_users CHANGE user_uid user_uid VARCHAR2(255);
-ALTER TABLE nag_shares_groups CHANGE group_uid group_uid VARCHAR2(255);
+ALTER TABLE nag_shares MODIFY share_owner VARCHAR2(255);
+ALTER TABLE nag_shares_users MODIFY user_uid VARCHAR2(255);
+ALTER TABLE nag_shares_groups MODIFY VARCHAR2(255);
-ALTER TABLE turba_shares CHANGE share_owner share_owner VARCHAR2(255);
-ALTER TABLE turba_shares_users CHANGE user_uid user_uid VARCHAR2(255);
-ALTER TABLE turba_shares_groups CHANGE group_uid group_uid VARCHAR2(255);
+ALTER TABLE turba_shares MODIFY share_owner VARCHAR2(255);
+ALTER TABLE turba_shares_users MODIFY user_uid VARCHAR2(255);
+ALTER TABLE turba_shares_groups MODIFY group_uid VARCHAR2(255);