Tender Wang <tndrw...@gmail.com> 于2025年4月14日周一 14:17写道：
> Hi, > > While I debug hashjoin codes, in estimate_multivariate_bucketsize(), I > find that > the list_copy(hashclauses) below is unnecessary if we have a single join > clause. > > List *clauses = list_copy(hashclauses); > ... > > I adjust the place of list_copy() call as the attached patch. > This can save some overhead of function calls and memory copies. > > Any thoughts? > > Hi Alexander, In the last thread, I found a minor optimization for the code in estimate_multivariate_bucketsize(). Adjust the place of list_copy() at the start of estimate_multivariate_bucketsize, and we can avoid unnecessarily creating a new list and memory copy if we have only a single hash clause. Do you think it's worth doing this? -- Thanks, Tender Wang
