mysql> select 'IND' type_cd,cust_id,lname name
-> FROM individual
-> union all
-> select 'BUS' type_cd,cust_id,name
-> from business;
+---------+---------+------------------------+
| type_cd | cust_id | name |
+---------+---------+------------------------+
| IND | 1 | Hadley |
| IND | 2 | Tingley |
| IND | 3 | Tucker |
| IND | 4 | Hayward |
| IND | 5 | Frasier |
| IND | 6 | Spencer |
| IND | 7 | Young |
| IND | 8 | Blake |
| IND | 9 | Farley |
| BUS | 10 | Chilton Engineering |
| BUS | 11 | Northeast Cooling Inc. |
| BUS | 12 | Superior Auto Body |
| BUS | 13 | AAA Insurance Inc. |
2.
mysql> SELECT emp_id
-> from employee
-> where assigned_branch_id=2
-> and (titile='Teller' OR title='Head Teller')
-> union
-> select distinct open_emp_id
-> from account
-> where open_bran_id=2;
这个是和集合,Union 是排序且排重的。
2.
except 在集合A中的除去素有的的zhzh
功夫数据,而exception all 则根据重负数据在B中出现的次数进行删除。
1.LMNOP QRST
2.LMNOPPQRST
3.p
4.LMNO ,去除B中的元素。
编写一个符合插叙,查找所有各人的客户以及雇员的姓氏和名字。
select fname,lname
from invividual
unoion
select fname,name
from emp
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