Upgrading SAP IQ: Uninstall the Old Version First
When upgrading SAP IQ on a Windows or Unix platform, be sure to uninstall the existing version before installing the new version. It is not recommended that you either install the new version over top of the existing installation or to a different folder on the same server. Failure to uninstall first could result in unexpected behavior running the new version.
On Windows, environment and registry settings are global, and are set by SAP IQ during installation. If you do not uninstall first, the existing SAP IQ environment and registry settings are automatically overwritten by the new version. Mixing settings and versions will result in errors. In addition, a new installation may introduce new settings while deprecating others. A new installation does not check for and remove deprecated settings. Failure to remove these settings could cause registry conflicts.
On Unix, if you have multiple versions installed, and you start an upgraded (newer) database with environment variables and binaries from different versions, you could encounter unexpected behavior or errors.
In short, uninstalling first guarantees a smooth upgrade process by ensuring all existing binaries, environment, and/or registry settings for the older version are removed before installing the new version.
Hi John,
I fully agree with your recommendation, but would like to add that on Unix systems, with some discipline, it is possible to keep various versions installed concurrently using different OS accounts. As you highlighted, the most relevant aspect of discipline is to make sure you're running database instances with the correct set of binaries. I consider this a reasonable approach for development environments.
On Windows, separating the accounts is at least more tricky, and the handling of environment variables (on system level) imo makes it impossible to keep multiple versions without messing them up.
That said, I'd strictly follow your recommendation on systems intended for one installation only and production systems in particular, not without backing up everything before clearing it, of course.
Cheers,
Volker
I prefer to keep the old version software for a few weeks or months - in case I need to revert to it.
on unix/linux:
/software/IQ <-- symbolic link that point to a specific version
/software/IQ-16.0
/software/IQ-15.4
That way I don't have to uninstall/reinstall the software. I just have to ensure the IQ.sh / SYBASE.sh point to /software/IQ as well as the infernal dbisql.rep file.
If I clone the software to another machine I use rsync
rsync -avh --progress --links /software/IQ* otherbox:/software/.
the --links parameter will preserve any symbolic links
jason