<\/p>\n
I was doing some NASTY SQL coding this evening (or squealing as Smiler<\/a> would say) and I got bogged down quite a while trying to get DISTINCT<\/font> and ORDER BY<\/font> working in the same query. The PostgreSQL<\/a> error message was not entirely clear and I must have misinterpreted it about 5 times before I finally figured out what it was so desperately trying to tell me!<\/p>\n Turns out that even if you don’t actually want to select the field you are sorting on in a query that uses the DISTINCT<\/font> keyword you still HAVE to include it in your SELECT<\/font> list or PSQL will have kittens!<\/p>\n BTW, I am aware that it is considered a ‘bad smell’ by some hard-core SQL programmers to use to DISTINCT<\/font> key word and I generally agree with their logic (why go to the effort of selecting a load of extra rows that you are just gonna prune off in the end?). However, I can’t for the life of me figure out how to get rid of the DISTINCT<\/font> in the query below, any insights you may have would be appreciated (looks at Bon)!<\/p>\n I was doing some NASTY SQL coding this evening (or squealing as Smiler would say) and I got bogged down quite a while trying to get DISTINCT and ORDER BY working in the same query. The PostgreSQL error message was not entirely clear and I must have misinterpreted it about 5 times before I finally […]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[1],"tags":[3,424],"series":[],"class_list":["post-155","post","type-post","status-publish","format-standard","hentry","category-uncategorized","tag-databases","tag-postgresql"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p7t9xK-2v","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.bartbusschots.ie\/s\/wp-json\/wp\/v2\/posts\/155","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bartbusschots.ie\/s\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bartbusschots.ie\/s\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bartbusschots.ie\/s\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bartbusschots.ie\/s\/wp-json\/wp\/v2\/comments?post=155"}],"version-history":[{"count":1,"href":"https:\/\/www.bartbusschots.ie\/s\/wp-json\/wp\/v2\/posts\/155\/revisions"}],"predecessor-version":[{"id":7411,"href":"https:\/\/www.bartbusschots.ie\/s\/wp-json\/wp\/v2\/posts\/155\/revisions\/7411"}],"wp:attachment":[{"href":"https:\/\/www.bartbusschots.ie\/s\/wp-json\/wp\/v2\/media?parent=155"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bartbusschots.ie\/s\/wp-json\/wp\/v2\/categories?post=155"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bartbusschots.ie\/s\/wp-json\/wp\/v2\/tags?post=155"},{"taxonomy":"series","embeddable":true,"href":"https:\/\/www.bartbusschots.ie\/s\/wp-json\/wp\/v2\/series?post=155"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}SELECT DISTINCT a.id AS assignmentId, a.name AS assignmentName, a.team_id AS teamId,
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