Re: [PG-11] Potential bug related to INCLUDE clause of CREATE INDEX

Hi Dave, 

I am working on a feature to support INCLUDE clause of index in PG-11. As per the documentation https://www.postgresql.org/docs/11/static/sql-createindex.html, columns listed in INCLUDE clause cannot also be present as index key columns. But I find different behaviour for below queries which are logically identical.

CREATE TABLE some_table

(

    id serial primary key,

    first_name character varying(45),

    last_name character varying

)

CREATE INDEX ind1

    ON public.some_table USING btree

    (id)

    INCLUDE(id)

    TABLESPACE pg_default;

This query fails with error

ERROR: included columns must not intersect with key columns

CREATE INDEX ind1

    ON public.some_table USING btree

    (id asc nulls last)

    INCLUDE(id)

    TABLESPACE pg_default;

This query passes and index is created.

Kindly let me know if I am missing anything.

--

Thanks and Regards,

Aditya Toshniwal

Software Engineer | EnterpriseDB Software Solutions | Pune

"Don't Complain about Heat, Plant a tree"