新手提问这2个查询怎么写？

Question

有下表：表1 employee eid   name department job email 
1001  李明  LUCK       EG 
1003  李杰  SBB        ITM 
10045 李燕  MTD        ENT 
10044 李明  LUKE       EG 
10023 小刚  SBB        EG 
20001 张清  MTD        ENT 表2.trainging 
courseID   EID        course      grade 
1          11045      T-SQL       60 
3          20460      java        23 
2          10001      Oracle      90 
1          20078      java        78 
3          30001      Oracle      60 
2          20048      T-SQL       32 问题： 
统计出各部门的人数和各部门姓“李”的人数，用一条SQL语句完成（用CASE语句） 问题：更新员工的Email,规则为：员工所在部门名称加员工姓名再加“@sina.com”,用一条SQL语句完成。如：李明的email为;SBB李明@sina.com

Answer 1

UPDATE EMPLOYEE T
SET T.EMAIL = T.DEPARTMENT||T.NAME||'@sina.com';
COMMIT;

Answer 2

SELECT DISTINCT DEPARTMENT,
                SUM(1),
                CASE
                    WHEN NAME LIKE '李%' THEN
                     1
                    ELSE
                     0
                END
  FROM EMPLOYEE

Answer 3

你这不对吧
SELECT  DEPARTMENT 部门,
                count(eid) 部门人数,sum(
                CASE
                    WHEN NAME LIKE '李%' THEN
                     1
                    ELSE
                     0
                END) 姓李的人数
  FROM EMPLOYEE
group by DEPARTMENT

Answer 4

你这不对吧
SELECT  DEPARTMENT 部门,
                count(eid) 部门人数,
                
                 sum(CASE
                    WHEN NAME LIKE '李%' THEN
                     1
                    ELSE
                     0
                END)   姓李人数
  FROM EMPLOYEE
  group by DEPARTMENT

Answer 5

你这不对吧
SELECT  DEPARTMENT 部门,
                count(eid) 部门人数,
                
                 sum(CASE
                    WHEN NAME LIKE '李%' THEN
                     1
                    ELSE
                     0
                END)   姓李人数
  FROM EMPLOYEE
  group by DEPARTMENT

Answer 6

你这不对吧
SELECT  DEPARTMENT 部门,
                count(eid) 部门人数,
                
                 sum(CASE
                    WHEN NAME LIKE '李%' THEN
                     1
                    ELSE
                     0
                END)   姓李人数
  FROM EMPLOYEE
  group by DEPARTMENT

Answer 7

select DEPARTMENT,count(*),count(case when name like'李%' then '1' else null end) from EMPLOYEE
    group by DEPARTMENTupdate EMPLOYEE set email = department||name||'@sina.com'

Answer 8

你这不对吧
SELECT  DEPARTMENT 部门,
                count(eid) 部门人数,
                
                 sum(CASE
                    WHEN NAME LIKE '李%' THEN
                     1
                    ELSE
                     0
                END)   姓李人数
  FROM EMPLOYEE
  group by DEPARTMENT