SQLZOO-练习答案SELECT basics/SELECT
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,'_%')