mysql - Calculating the largest out of multiple averages - SQL -

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i have table, contains number of cd entrys, complete names, price , genre. trying return average price genre, average price of "rock", "pop", "alternative rock", "electronica", & "electro house". after then trying have automatically display genre highest average price.

the table called "cd" table columns cd.id, cd.title, cd.price & cd.genre

i have tried using method shown below.. trying establish different averages 3 of genres..

select ((select avg(cdprice) cd                 cd.genre = 'rock') rock,        (select avg(cdprice) cd                 cd.genre = 'pop') pop,        (select avg(cdprice) cd                 cd.genre = 'electro') electro);

however might missing method, not overly familiar "as" command , correct usage.

rows (almost) easier columns. want first avg price each genre:

select     avg(cdprice) price, genre cd group genre

the second part filter 1 highest avg(cdprice). there's couple of different options here, , depends on requirements happens if 2 genres have equivalent price? want both or random? simple way latter order set , select first row:

select top(1)     avg(cdprice) price, genre cd group genre order     price desc

if want both rows in case of ties, first find max of set, , self-join find matches:

select price, genre (    --first table our avg price per genre    select avg(cdprice) price, genre cd group genre ) avg join (    --second table maximum avg price    select max(price) (        select avg(cdprice) price cd group genre    ) avg2 ) max on    --join on price find genres have maximum price    avg.price = max.price

or, take advantage of having clause write (arguably) little cleaner:

select avg(cdprice) price, genre cd group genre having avg(cdprice) = (   select max(price) (select avg(cdprice) price cd group genre) )

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