1.單表查詢

員工表empinfo結構如下：

create table empinfo(
	Fempno varchar(20) not null primary key,
	Fempname varchar(20) not null,
	Fage number not null,
	Fsalary number  not null
);

fsalary > 9999 and fage >35

fsalary > 9999 and fage < 35

fsalary < 9999 and fage >35

fsalart < 9999 and fage > 35

select sum(case when tt.fsalary >9999 and tt.fage >35 
			then 1
			else 0
			end
) as  "fsalary > 9999 and fage > 35",sum(case when tt.fsalary > 9999 and tt.fage <35
			then 1
			else 0
			end
) as "fsalary > 9999 and fage < 35",sum(case when tt.fsalary < 9999 and tt.fage > 35
			then 1
			else 0
			end
) as "fsalary < 9999 and fage > 35",sum(case when tt.fsalary < 9999 and fage <35
			then 1
			else 0
			end
)as "fsalary < 9999 and fage < 35"
from empinfo tt
 

2.多表聯合查詢

請用一個SQL語句得出結果：從table1、table2中取出如table3所列格式資料（注意提供的資料及結果不準確，只是作為一個格式參考）。

表結構如下：

table1：

月份(month)		部門(dep)		業績(yj)
一月份			01				10
一月份			02				10
一月份			03				5
二月份			02				8
二月份			04				9
三月份			03				8

部門(dep)			部門名稱(dname)
01					國內業務一部
02					國內業務二部
03					國內業務三部
04					國內業務部

table3：

部門(dep)		一月份		二月份		三月份
01				10			null		null
02				10			8			null
03				null		5			8
04				null		null		9
 

select a.dep,sum(case when b.month=1 then b.yj else 0 end) as "一月份",
sum(case when b.month=2 then b.yj else 0 end) as "二月份",
sum(case when b.month=3 then b.yj else 0 end) as "三月份",
sum(case when b.month=4 then b.yj else 0 end) as "四月份",
sum(case when b.month=5 then b.yj else 0 end) as "五月份",
sum(case when b.month=6 then b.yj else 0 end) as "六月份",
sum(case when b.month=7 then b.yj else 0 end) as "七月份",
sum(case when b.month=8 then b.yj else 0 end) as "八月份",
sum(case when b.month=9 then b.yj else 0 end) as "九月份",
sum(case when b.month=10 then b.yj else 0 end) as "十月份",
sum(case when b.month=11 then b.yj else 0 end) as "十一月份",
sum(case when b.month=12 then b.yj else 0 end) as "十二月份",
from table2 a left join table1 b on a.dep=b.dep