Mysql: How to select distinct values from a database column
My goal is to select value from "EmbedImgDimension" column where in lots of duplicated values are present.
I have used the following query
select
distinct EmbedImgId,
VideoID,
EmbedImgHeight,
EmbedImgWidth,
EmbedImgFileName,
concat(embedimgwidth,' x ',embedimgheight) as EmbedImgDimension
from embedimages
inner join Video on Video.schoolid=#Value#
where embedimages.isdeleted=0 order by embedimages.embedimgwidth asc;
wat modification should i make in this query so as to select unique values from t开发者_如何学Pythonhe "EmbedImgDimension" column.Any help would be deeply appreciated.
Thanks.
select
distinct concat(embedimgwidth,' x ',embedimgheight) as EmbedImgDimension
from embedimages
inner join Video on Video.schoolid=#Value#
where embedimages.isdeleted=0 order by embedimages.embedimgwidth asc;
update
saying you also want distinct video ids is a logical problem. you want to get a result in which each dimension appears only once, right? then, how can you expect to also get all the distinct videoID results? imagine you have
videoid dimension
1 1x1
2 1x1
3 2x2
4 2x2
maybe you can tell me which result you'd like to get. but you're either going to get 1x1 and 2x2, or you're going to get 1,2,3,4 - the moment you want dimension uniqueness, you can't also get all the distinct videoids, see what I mean?
Use the distinct
keyword on the EmbedImgDimension
column.
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