Lazy Projection

[clv100]

Can anyone explain what the term "lazy" projection means? Thanks!

[JimKnicely]

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:

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)

Notice that "createtype(L)" syntax. The "L" stands for "Lazy".

[clv100]

Thank you for the information!