How to create subquery with distinct in Oracle SQL -


i have following 2 oracle sql queries work well:

select count(seg_id) totaluniquesegments car_rental_services;  select distinct seg_id car_rental_services;

but need combine them. i'd count consider unique seg_id.

this i've tried:

select count(seg_id)into totaluniquesegments car_rental_services seg_id in (select distinct seg_id car_rental_services);

but i'm getting error 'missing expression'. should simple i'm not experienced. thanks.

edit: count(seg_id)into changed count(seg_id) into (with space). error 'missing expression'

try this,

select count(distinct seg_id) car_rental_services;

use below query, if want demonstrate same using sub-query. 

select count(*) from(      select distinct seg_id         car_rental_services      );

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