On Tue, May 5, 2020 at 10:31 AM Dilip Kumar <dilipbal...@gmail.com> wrote: > > On Tue, May 5, 2020 at 10:25 AM Amit Kapila <amit.kapil...@gmail.com> wrote: > > > > On Tue, May 5, 2020 at 9:27 AM Dilip Kumar <dilipbal...@gmail.com> wrote: > > > > > > On Mon, May 4, 2020 at 5:16 PM Amit Kapila <amit.kapil...@gmail.com> > > > wrote: > > > > > > > > On Fri, May 1, 2020 at 8:41 PM Dilip Kumar <dilipbal...@gmail.com> > > > > wrote: > > > > > > > > > > > > 5. Shouldn't we add a check in table_scan_sample_next_block and > > > > table_scan_sample_next_tuple APIs as well? > > > > > > I am not sure that we need to do that, Because generally, we want to > > > avoid getting any wrong system table tuple which we can use for taking > > > some decision or decode tuple. But, I don't think that > > > table_scan_sample falls under that category. > > > > > > > Hmm, I am asking a check similar to what you have in function > > table_scan_bitmap_next_block(), can't we have that one? > > Yeah we can put that and there is no harm in that, but my point is > the table_scan_bitmap_next_block and other functions where I have put > the check are used for fetching the tuple which can be used for > decoding tuple or taking some decision, but IMHO, > table_scan_sample_next_tuple is only used for analyzing the table. >
These will be used in TABLESAMPLE scan. Try something like "select c1 from t1 TABLESAMPLE BERNOULLI(30);". So, I guess these APIs can also be used to fetch the tuple. -- With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com
