SQLZOO-练习答案SELECT basics/SELECT names

SELECT basics/SELECT names 练习答案

11、SELECT name fromworld

where name=capital

12、select name fromworld where capital like concat(NAME,’ City')

说明：concat（）意为将字符链接起来。注意‘city’前需要留一个空格，否则答案错误。

13、selectcapital,name

from world

where capital like concat('%',name,'%')

说明：找出首都名字含有国家名称的国家。Concat（）此处仍然为连接字符的函数，“%”为通配符，此处的百分号通配符需要添加用单引号。另外，按照题意，挑选顺序应该是先capital，然后name。

14、selectcapital,name

from world

where capital like concat('%',name,'%') andcapital not like name

或者

Select capital,name

From world

Where capital like concat(‘%’,name,’%’) andcapital!=name

15、不明白，未知，待解

Q:

For Monaco-Ville the name is Monaco and theextension is -Ville.

Show the name and the extension where thecapital is an extension of name of the country.

You can use the SQL function REPLACE.

A:

SELECT name, REPLACE(capital,name,'') AS extFROM world WHERE capital LIKE concat(name,'_%')

或者

SELECT name, REPLACE(capital, name, '') FROMworld WHERE capital LIKE concat('%', name, '%') AND capital > name

或者

selectname,mid(replace(capital,name,'1'),2) 

from world 

where capital like concat(name,'_%')