Postgres if 문 내부 함수 삽입 값

Question

이 함수를 작동시킬 수 있습니까? 나는 If 문 안에 Postgres 함수로 질의를 삽입한다.

어떤 방법이 있습니까?

CREATE FUNCTION proc_api_consumer_audit_insert() 
    RETURNS TRIGGER AS $api_consumer$ 
    BEGIN 
     INSERT INTO api_consumer_audit(api_consumer_id, change_type, changed_by, changed_date, business_id_old, business_id_new, name_old, name_new, api_callback_url_old, api_callback_url_new, application_base_url_old, application_base_url_new, authorization_callback_url_old, authorization_callback_url_new, status_old, status_new) 
     VALUES(NEW.id, 'INSERT', (IF NEW.created_by=null THEN CURRENT_USER ELSE NEW.created_by END IF;), CURRENT_TIMESTAMP, null, NEW.business_id, null, NEW.name, null, NEW.api_callback_url, null, NEW.application_base_url, null, NEW.authorization_callback_url, null, NEW.status); 
     RETURN NEW; 
    END; 
    $api_consumer$ LANGUAGE plpgsql; 

Answer 1

SQL에 IF이 없습니다.

INSERT INTO api_consumer_audit(...) 
VALUES (NEW.id, 
     'INSERT', 
     coalesce(new.created_by, current_user), 
     ...); 

과 같을 것이다 CASE 표현식과 같은 :

INSERT INTO api_consumer_audit(...) 
VALUES (NEW.id, 
     'INSERT', 
     case 
      when new.created_by IS NOT NULL then new.created_by 
      else current_user 
     end, 
     ...);