Undroppable columns in table

Hi all, we're using IDS 11.70.FC5 in a DWH environment and did a table-level restore for one of the fact tables. This seemed to work but left two additional columns ifx_tlr_rowid and ifx_tlr_partnum on the table which I wanted to get rid of. As I found out, it is not possible to drop these, or any other column of this table any more! Any 'ALTER TABLE tablename DROP column_name' gives no error, but has no effect and the column column_name still exists. I'm DBA (but not 'informix') on this DB and can rename columns, add new ones and drop them again for that table. Is this a known bug if the restore failed somehow? Some web search found very little information about the ifx_tlr columns and for what they are used. Also, I did not found any special settings for the columns in syscolumns, syscolattribs, syscoldepend, syscolauth. Thanks in advance, Jens

Original post: Hi all, we're using IDS 11.70.FC5 in a DWH environment and did a table-level restore for one of the fact tables. This seemed to work but left two additional columns ifx_tlr_rowid and ifx_tlr_partnum on the table which I wanted to get rid of. As I found out, it is not possible to drop these, or any other column of this table any more! Any 'ALTER TABLE tablename DROP column_name' gives no error, but has no effect and the column column_name still exists. I'm DBA (but not 'informix') on this DB and can rename columns, add new ones and drop them again for that table. Is this a known bug if the restore failed somehow? Some web search found very little information about the ifx_tlr columns and for what they are used. Also, I did not found any special settings for the columns in syscolumns, syscolattribs, syscoldepend, syscolauth. Thanks in advance, Jens Response: This sounds like it could be a bug. I didn't turn one up with my quick look. The 2 columns you mention are definitely part of the table level restore, but from my quick look at code, it looks like they should be added in the start and dropped at the end. It looks like it might log something about the the alter (if it skipped undoing the alter) in the default msg.log file (AC_MSGPATH from the archecker config file). However, I'm not sure how you get a table into a state where you can add new columns and drop them, but not drop existing columns. So I'm not sure what's wrong that would be preventing the alter table drop command from working, and what's worse is if it's really not returning an error but not actually doing anything. I'd recommend opening aPMR with support for this. Jacques Renaut IBM Informix Advanced Support APD Team