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POGet "latest" row after GROUP BY over multiple tables
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  1. POGet "latest" row after GROUP BY over multiple tables
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    copied!<p>I'd preferably like to first query listed below and just group by <code>stories.id</code>, but I get the following error:</p> <p><code>ERROR: column "u.first_name" must appear in the GROUP BY clause or be used in an aggregate function LINE 1: SELECT "s".*, "u"."first_name", "u"."last_name", ("i"."filen...</code></p> <p>The second query works but does not group by <code>stories.id</code> and generates the wrong results. Is it possible to select from multiple tables and not group by all of them?</p> <p>The table <code>panels</code> also has a column <code>updated_at</code>. I would like to get the newest <code>file</code> per story according to <code>panels.updated_at</code>.</p> <pre><code> SELECT "s".*, "u"."first_name", "u"."last_name", ("i"."filename" || '.' || "i"."extension") AS "file" FROM "stories" "s" LEFT JOIN "panels" "p" ON("p"."story_id" = "s"."id") LEFT JOIN "users" "u" ON("s"."user_id" = "u"."uid") LEFT JOIN "images" "i" ON ("p"."image_id" = "i"."id") WHERE "s"."complete" = false AND "s"."created_by" = 205700489 GROUP BY "s"."id", ORDER BY "s"."created_at" DESC </code></pre> <hr> <pre><code> SELECT "s".*, "u"."first_name", "u"."last_name", ("i"."filename" || '.' || "i"."extension") AS "file" FROM "stories" "s" LEFT JOIN "panels" "p" ON("p"."story_id" = "s"."id") LEFT JOIN "users" "u" ON("s"."user_id" = "u"."uid") LEFT JOIN "images" "i" ON ("p"."image_id" = "i"."id") WHERE "s"."complete" = false AND "s"."created_by" = 205700489 GROUP BY "s"."id", "u"."first_name", "u"."last_name", "i"."filename", "i"."extension" ORDER BY "s"."created_at" DESC </code></pre>
 

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