tree 7f8fd6ce63d27a742186c5f821d0a928a334c72d
parent b036870c8cb1dd55fe7de1113770316f605f3051
author Wail Alkowaileet <wael.y.k@gmail.com> 1683674694 -0700
committer Wail Alkowaileet <wael.y.k@gmail.com> 1683818081 +0000

[ASTERIXDB-3180][COMP][RT] Apply filter before assembling columnar datasets

- user model changes: no
- storage format changes: no
- interface changes: yes

Details:
This patch implements an idea by Mike Carey, which says
let's use the columns as a "poorman" index. The condition
expression of SELECT is pushed down to data-scan and
the following is performed for each mega-leaf node:

1- Read all the columns involved in the SELECT condition expression.
2- Look for a tuple that satisfies the condition
  - If none exists, skip reading the rest of the columns
  - If at least one exists, read the rest of the columns
3- For each subsequent call to next() in the LSM cursor,
   check whether the returned tuple satisfies the condition
  - If yes, assemble and return the tuple
  - If no, skip and go to the next tuple and repeat

Change-Id: Ia83b839633d83ac6e3ffb4340a1d144daa0b299d
Reviewed-on: https://asterix-gerrit.ics.uci.edu/c/asterixdb/+/17510
Integration-Tests: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Reviewed-by: Wail Alkowaileet <wael.y.k@gmail.com>
Reviewed-by: Ali Alsuliman <ali.al.solaiman@gmail.com>