sql - SELECT Top 1 ID, DISTINCT Field -


i have table sample table follows:

id | city -------------- 1  | new york 2  | san francisco 3  | new york 4  | los angeles 5  | atlanta

i select distinct city , top id each. e.g., conceptually following

select top 1 id, distinct city cities

should give me:

id | city -------------- 1  | new york 2  | san francisco 4  | los angeles 5  | atlanta

because new york appears twice, it's taken first id 1 in instance.

but error:

column 'cities.id' invalid in select list because not contained in either aggregate function or group clause.

try way:

select min(id), city cities group city

min function used choose 1 of id 2 new york cities.


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