Re: [HACKERS] Partition : Append node over a single SeqScan
Hi, On Wed, Jul 5, 2017 at 3:58 PM, Ashutosh Bapat wrote: > On Wed, Jul 5, 2017 at 3:48 PM, Ashutosh Sharma wrote: >> Hi All, >> >> Today while exploring a bit on Range table partitioning, I could see >> that even if scan is performed on a single partition, the plan node >> has Append node in it. Isn't it a bug? > > No. See following comment from create_append_plan() > 1045 /* > 1046 * XXX ideally, if there's just one child, we'd not bother to > generate an > 1047 * Append node but just return the single child. At the > moment this does > 1048 * not work because the varno of the child scan plan won't match the > 1049 * parent-rel Vars it'll be asked to emit. > 1050 */ > Thanks for the information. -- With Regards, Ashutosh Sharma EnterpriseDB:http://www.enterprisedb.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] Partition : Append node over a single SeqScan
On Wed, Jul 5, 2017 at 3:48 PM, Ashutosh Sharma wrote: > Hi All, > > Today while exploring a bit on Range table partitioning, I could see > that even if scan is performed on a single partition, the plan node > has Append node in it. Isn't it a bug? No. See following comment from create_append_plan() 1045 /* 1046 * XXX ideally, if there's just one child, we'd not bother to generate an 1047 * Append node but just return the single child. At the moment this does 1048 * not work because the varno of the child scan plan won't match the 1049 * parent-rel Vars it'll be asked to emit. 1050 */ -- Best Wishes, Ashutosh Bapat EnterpriseDB Corporation The Postgres Database Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
