Add column

Folks, IDS 11.70 A big table with hundreds of millions rows. When adding a column, from performance point of view, any potential preference or difference .... if the column would be added at front, at end or in the middle of existing columns? Thanks, Frank --047d7b5d4e3c53391804e97e7217

No difference. Putting it adjacent to other columns that will be fetched in the same projection clause may promote certain processor specific memory optimizations processing fetches, but that's it and minor. As far as the ALTER is concerned, no difference. The datatype being added is more important as certain types cannot be added to a table using an in-place alter and will require locking the table until all rows have been modified to the new schema. Art Art S. Kagel, Principal Consultant Advanced DataTools (www.advancedatatools.com) Blog: http://informix-myview.blogspot.com/ Disclaimer: Please keep in mind that my own opinions are my own opinions and do not reflect on my employer, Advanced DataTools, the IIUG, nor any other organization with which I am associated either explicitly, implicitly, or by inference. Neither do those opinions reflect those of other individuals affiliated with any entity with which I am affiliated nor those of the entities themselves. On Thu, Oct 24, 2013 at 11:50 AM, FRANK <yunyaoqu@gmail.com> wrote: > Folks, > > IDS 11.70 > > A big table with hundreds of millions rows. When adding a column, from > performance point of view, any potential preference or difference .... if > the column would be added at front, at end or in the middle of existing > columns? > > Thanks, > Frank > > --047d7b5d4e3c53391804e97e7217 > > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. > > --089e01176915d2825f04e97f6caa