mysql - Query based off one element -

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i given following database schema

cows (cowid, cowname, cowage) cowpurchaser (purchaserid, name, address) purchaserecord (purchaserid, cowid, year)

for each year, cow purchaser "farmland" purchased atleast 1 cow, find number of cows purchased. output set of tuples, indicates year , number of cows purchased "farmland"

i not sure how approach this. tried

select (pr.year, count(c.name)) purchaserecord pr, cowpurchaser cp, cows c cp.name = "farmland" , count(c.name) >= 1

this not giving result want. doing wrong? how can fix it?

select pr.year, count(c.name) purchaserecord pr      inner join cowpurchaser cp on pr.purchaserid=cp.purchaserid      inner join cows c on pr.cowid=c.cowid cp.name = "farmland"  group pr.year having count(c.name) >= 1

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