Lazy Projection
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Lazy Projection
Can anyone explain what the term "lazy" projection means? Thanks!
- JimKnicely
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Re: Lazy Projection
Hi,
I believe it is just a reference to when Vertcia creates a super-projection for you (because you were too lazy to create you own )
Example:
Notice that "createtype(L)" syntax. The "L" stands for "Lazy".
I believe it is just a reference to when Vertcia creates a super-projection for you (because you were too lazy to create you own )
Example:
Code: Select all
dbadmin=> create table lazy (c int);
CREATE TABLE
dbadmin=> insert into lazy values (1);
OUTPUT
--------
1
(1 row)
dbadmin=> select export_objects('','lazy');
export_objects
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
CREATE TABLE public.lazy
(
c int
);
CREATE PROJECTION public.lazy_super /*+basename(lazy),createtype(L)*/
(
c
)
AS
SELECT lazy.c
FROM public.lazy
ORDER BY lazy.c
SEGMENTED BY hash(lazy.c) ALL NODES OFFSET 1;
SELECT MARK_DESIGN_KSAFE(1);
(1 row)
Jim Knicely
Note: I work for Vertica. My views, opinions, and thoughts expressed here do not represent those of my employer.
Note: I work for Vertica. My views, opinions, and thoughts expressed here do not represent those of my employer.
Re: Lazy Projection
Thank you for the information!