Question

sql语句的写法——把两个数相除（Oracle）

select count(*) as a from...
select count(*) as b from...
我想求a/b的值，怎么用一条sql语句写出来呢？
Dual 是 Oracle中的一个实际存在的表，任何用户均可读取，常用在没有目标表的Select语句块中

--查看当前连接用户SQL> select user from dual;USER------------------------------SYSTEM--查看当前日期、时间SQL> select sysdate from dual;SYSDATE-----------2007-1-24 1SQL> select to_char(sysdate,'yyyy-mm-dd hh24:mi:ss') from dual;TO_CHAR(SYSDATE,'YYYY-MM-DDHH2------------------------------2007-01-24 15:02:47--当作计算器用SQL> select 1+2 from dual;1+2----------3--查看序列值SQL> create sequence aaa increment by 1 start with 1;SQL> select aaa.nextval from dual;NEXTVAL----------1SQL> select aaa.currval from dual;CURRVAL----------1

Answer 1

select (select count(*) as a from...)/(select count(*) as b from...
) from dual