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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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