Siebel 8.1.1.4 DDL Sync issue

Hello,If suppose the columns in a custom table are inactivated in Siebel Tools, does the DDL Sync not issue a drop statement for those columns on physical schema? 

In our development environment, some of the columns in a custom table were created and applied on DB, but later on they were inactivated in Tools. The inactivation part was directly done connecting to the server Tools. 

When we did a  DDL Sync, we expected that the columns will be dropped from the physical schema as well, but it did not drop them. We tried to do a generate DDL on the modified table and even in DDL, there was no alter table statement generated to drop these inactive columns. Please let us know how to drop these inactive columns on DB using a DDL sync.