Re: ALTER table - how muc

Ih> In attempting to unsuccessfully alter some large Informix tables, Ih> we've run into failures. The question arises, is how much Ih> free space is needed, as indicated by tbcheck -pe? Ih> Specifically, if my first allocation was 10,000 blocks, Ih> and the next size is 1,000 blocks, will Informix require Ih> a section of 10,000 blocks to do the alter in??? Ih> What is the first next section were adjacent to the original Ih> 10,000 - now, I believe, I have 11,000 blocks - the initial Ih> allocation is not stored by Informix - so I Ih> presume that I would need 11,000 blocks??? I think when ALTER TABLE is run, it renames the original table, then copies the structure with modifications (reserving room for data from the old table), then copies data from matching columns from the renamed original table to the new table. The last step is to drop the old table. If I'm right, this means you'd need 11,000 blocks in addition to what you already have ... Hope I'm not lost in space on this. Bill Williams ... I haven't lost my mind; it's backed up on tape somewhere! ___ Blue Wave/QWK v2.12 ---- +------------------------------------------------------------------------+ | Data Warp Premium BBS (713) 355-6107 HST/V.32bis | | Spring / Houston, Texas Multi-line, multi-gig PCBoard BBS | +------------------------------------------------------------------------+