Au d??tour d’une rencontre avec un guru du SQL, j’ai pu admirer le code suivant, permettant d’effacer tous le doublon d’une table. Imaginons une table (aTable) avec une seule colonne (aNumber), aucune cl??, mais avec plusieurs lignes contenant la m??me valeur :<\/P>
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1
1
2
1
3
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3
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1<\/P>
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Le but est du supprimer tous les doublons, ceci en une seule requ??te. Vous avez la r??ponse ?<\/P>
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Voici le code SQL :<\/P>
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set<\/SPAN> rowcount 1 <\/P> <\/P> Some couple of weeks ago, I had the opportunity to meet SQL guru, and I have seen a very nice SQL code, deleting duplicates rows in a table. Let’s imagine a table (aTable) with only one field (aNumber), without any key but multiple rows with the same value :<\/EM><\/P> 1 The goal is to delete duplicate values in only one SQL request. You have the answed ?<\/EM><\/P> Here is the code :<\/EM><\/P> set<\/SPAN> rowcount 1 Un exemple de code SQL vraiment tr??s beau ?? voir. An example of a very nice SQL code.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[1],"tags":[],"class_list":["post-1824","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/www.peneveyre.com\/en\/wp-json\/wp\/v2\/posts\/1824","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.peneveyre.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.peneveyre.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.peneveyre.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.peneveyre.com\/en\/wp-json\/wp\/v2\/comments?post=1824"}],"version-history":[{"count":0,"href":"https:\/\/www.peneveyre.com\/en\/wp-json\/wp\/v2\/posts\/1824\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.peneveyre.com\/en\/wp-json\/wp\/v2\/media?parent=1824"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.peneveyre.com\/en\/wp-json\/wp\/v2\/categories?post=1824"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.peneveyre.com\/en\/wp-json\/wp\/v2\/tags?post=1824"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
select<\/SPAN> 1
while<\/SPAN> @@rowcount<\/SPAN> > 0
delete<\/SPAN> test
where<\/SPAN> 1 < (select<\/SPAN> count<\/SPAN>(*) from<\/SPAN> test t2 where<\/SPAN> test.id = t2.id)
set<\/SPAN> rowcount 0
<\/SPAN><\/P>
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1
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1
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1<\/EM><\/P>
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select<\/SPAN> 1
while<\/SPAN> @@rowcount<\/SPAN> > 0
delete<\/SPAN> test
where<\/SPAN> 1 < (select<\/SPAN> count<\/SPAN>(*) from<\/SPAN> test t2 where<\/SPAN> test.id = t2.id)
set<\/SPAN> rowcount 0<\/SPAN>
<\/SPAN><\/P><\/SPAN><\/p>\n","protected":false},"excerpt":{"rendered":"