hudson can set the days to keep builds,but maybe a long time passed,the previous build result maybe deleted,however I want to get the build result of this build ,so I want to rebuild the build_number, any way can build it?
I don't think that this would really make sense. A build represents a point in time. e.g. checkout from source control and build / test what is present at that point in time.
You could of course create a job that checks out a specific tag from your source control (depending on your SCM system) and builds based on that, but that would likely be a specialized parametrized job.
sometime I want the build result at that point to compare to the latest result.
our SCM system is git,we use repo to upload source code ,there is no tag in the source control,there is no way to build the previous build_number?