Postgresql日期间隔和SELECT语句

Question

我使用portgres 我有这个运行成功的查询。

SELECT count(distinct(salary.id)) AS nbr
FROM salary salary  
 WHERE  salary.status ='P'

 AND (salary.date_jc_salary is NULL  and case priority_salary  
 WHEN 'N' THEN current_date > date_send_salary +interval '36'  hour  
 WHEN 'U'  THEN current_date > date_send_salary +interval '24'  hour 
 ELSE current_date > date_send_salary +interval '36'  hour end 
 OR (salary.date_jc_salary is NOT NULL 
 AND to_char(current_date , 'yyyy/MM/dd') >= to_char(date_jc_salary , 'yyyy/MM/dd')

 ) )  

我的问题是我想让子查询具有interval的值。

意思是进行此查询：

SELECT count(distinct(salary.id)) AS nbr
FROM salary salary  
 WHERE  salary.status ='P'

 AND (salary.date_jc_salary is NULL  and case priority_salary  
 WHEN 'N' THEN current_date > date_send_salary +interval '36'  hour  
 WHEN 'U'  THEN current_date > date_send_salary +interval '24'  hour 
 ELSE current_date > date_send_salary +interval '36'  hour end 
 OR (salary.date_jc_salary is NOT NULL 
and current_date > salary.date_jc_salary +interval select salary.date_jc_salary::date - now()::date  day  
 ) )  

所以只改变这一行：

and current_date > salary.date_jc_salary +interval select salary.date_jc_salary::date - now()::date  day  

但我有这个错误：

  syntax error at or near "select"
LINE 10: ...rrent_date > salary.date_jc_salary  -interval select sal...
                                                              ^

********** Error **********

ERROR: syntax error at or near "select"
SQL state: 42601
Character: 847

目标是将日期 date_jc_salary 添加为 date_jc_salary 与当前日期之间的差异