簡單的就不寫了，只記錄卡殼的。持更。
如果有誤闖進來的，不要參考我的，沒有參考價值，跪了。
select name
from world
where name like capital
select name
from world
where name = capital
select name
from world
where capital like concat(name,
' city'
)
select capital, name
from world
where capital like concat(
'%', name,
'%')
select name, capital
from world
where capital like concat(name,
'_',
'%')
--寫成concat(name, '_%')就好
select name,capital from world
where capital like concat(name,
'%')
and capital != name;
select name,
replace
(capital,name,'')
as ext
from world
where capital like concat(name,
'_',
'%')
我是這麼寫的，也通過了就。
select name,population,area
from world
where
(area >=
3000000
or population >=
250000000
)and name notin(
'united states'
,'india'
,'china'
)
select * from test where a xor b
如果a為真，則查出不滿足b條件資料;
如果a為假，則查出滿足b條件資料；
select name, population, area from world
where area >
3000000
xor population >
250000000
;
select name,
case
when continent=
'caribbean'
then
'north america'
when continent=
'oceania'
then
'australasia'
else continent end
from world
where name like
'n%'
select name,
case
when continent in
('europe'
,'asia'
)then
'eurasia'
when continent in
('north america'
,'south america'
,'caribbean'
)then
'america'
else continent end
from world
where name like
'a%'
or name like
'b%'
put the continents right…
一直做不對是直接除以了題目裡的8000w。阿西。
select name,concat(
round
(population/
(select population from world where name =
'germany')*
100,0)
,'%'
)from world
where continent =
'europe'
隱隱約約懂了，又隱隱約約不懂。
select continent, name, area
from world x
where area >=
all(
select area from world y
where y.continent=x.continent
and area>
0)
不會做看了別人的答案啊原來這個也可以用大於小於比較啊。
select continent,name from world x
where name <=
all(
select name from world y
where y.continent = x.continent)
;
select continent,name from world
where name in
(select
min(name)
from world
group
by continent)
;
還要好好看看啊
select name,continent,population
from world x
where
25000000
>
all(
select population
from world y
where x.continent = y.continent
group
by continent
)
前幾遍沒有寫y.name != x.name
select name, continent
from world x
where population >=
all(
select population*
3from world y
where x.continent = y.continent
and y.name != x.name )
select basics
quiz
select from world 13
quiz
select from nobel
quiz
select in select 有空再寫一遍
quiz
sum and count
quiz
寫完了
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