{"id":3331,"date":"2016-03-08T02:53:45","date_gmt":"2016-03-08T02:53:45","guid":{"rendered":"http:\/\/www.garysieling.com\/blog\/?p=3331"},"modified":"2016-03-08T02:53:45","modified_gmt":"2016-03-08T02:53:45","slug":"rethinkdb-select-distinct-example","status":"publish","type":"post","link":"https:\/\/www.garysieling.com\/blog\/rethinkdb-select-distinct-example\/","title":{"rendered":"RethinkDB: SELECT DISTINCT example"},"content":{"rendered":"

Using “distinct” in RethinkDB is as simple as adding an additional predicate:<\/p>\n

r.db('test')\n .table('salaries')\n .pluck('role')\n .distinct()\n<\/pre>\n
3 rows returned in 42ms.<\/p>\n
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role<\/div>\n<\/div>\n<\/td>\n<\/tr>\n
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1<\/div>\n<\/td>\n
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undefined<\/div>\n<\/div>\n<\/td>\n<\/tr>\n
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2<\/div>\n<\/td>\n
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Designer<\/div>\n<\/div>\n<\/td>\n<\/tr>\n
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3<\/div>\n<\/td>\n
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Manager<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n
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You can add as many columns as you need:<\/p>\n
r.db('test')\n .table('salaries')\n .pluck('role', 'level')\n .distinct()\n<\/pre>\n
7 rows returned in 42ms.<\/p>\n
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level<\/div>\n<\/div>\n<\/td>\n
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role<\/div>\n<\/div>\n<\/td>\n<\/tr>\n
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1<\/div>\n<\/td>\n
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undefined<\/div>\n<\/div>\n<\/td>\n
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Manager<\/div>\n<\/div>\n<\/td>\n<\/tr>\n
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Designer<\/div>\n<\/div>\n<\/td>\n<\/tr>\n
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5<\/div>\n<\/td>\n
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Manager<\/div>\n<\/div>\n<\/td>\n<\/tr>\n
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3<\/div>\n<\/div>\n<\/td>\n
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Designer<\/div>\n<\/div>\n<\/td>\n<\/tr>\n
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Manager<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
Also, unlike some other predicates, this does not transform the data into some weird other data type, so you can operate on it as you would any other:<\/p>\n
\nr.db('test')\n .table('salaries')\n .pluck('role', 'level')\n .distinct()\n .group('role')\n .count()\n<\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n
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3 rows returned in 78ms.<\/p>\n<\/div>\n
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group<\/div>\n<\/div>\n<\/td>\n
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reduction<\/div>\n<\/div>\n<\/td>\n<\/tr>\n
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3<\/div>\n<\/td>\n
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Manager<\/div>\n<\/div>\n<\/td>\n
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3<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n
<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"
Using “distinct” in RethinkDB is as simple as adding an additional predicate: r.db(‘test’) .table(‘salaries’) .pluck(‘role’) .distinct() 3 rows returned in 42ms. role 1 undefined 2 Designer 3 Manager You can add as many columns as you need: r.db(‘test’) .table(‘salaries’) .pluck(‘role’, ‘level’) .distinct() 7 rows returned in 42ms. level role 1 undefined undefined 2 1 Designer … <\/p>\n
Continue reading “RethinkDB: SELECT DISTINCT example”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[4],"tags":[160,302,462,466,523],"aioseo_notices":[],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/www.garysieling.com\/blog\/wp-json\/wp\/v2\/posts\/3331"}],"collection":[{"href":"https:\/\/www.garysieling.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.garysieling.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.garysieling.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.garysieling.com\/blog\/wp-json\/wp\/v2\/comments?post=3331"}],"version-history":[{"count":0,"href":"https:\/\/www.garysieling.com\/blog\/wp-json\/wp\/v2\/posts\/3331\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.garysieling.com\/blog\/wp-json\/wp\/v2\/media?parent=3331"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.garysieling.com\/blog\/wp-json\/wp\/v2\/categories?post=3331"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.garysieling.com\/blog\/wp-json\/wp\/v2\/tags?post=3331"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}