{"id":9248,"date":"2018-09-05T09:11:35","date_gmt":"2018-09-05T09:11:35","guid":{"rendered":"http:\/\/www.gencayyildiz.com\/blog\/?p=9248"},"modified":"2018-09-05T09:11:35","modified_gmt":"2018-09-05T09:11:35","slug":"mongodb-gruplama-inceliklerigroup-operatoru","status":"publish","type":"post","link":"https:\/\/www.gencayyildiz.com\/blog\/mongodb-gruplama-inceliklerigroup-operatoru\/","title":{"rendered":"MongoDB – Gruplama \u0130ncelikleri($group Operat\u00f6r\u00fc)"},"content":{"rendered":"

<\/div>\n

Merhaba,<\/p>\n

\u00d6nceki yaz\u0131lar\u0131mdan NoSQL \u2013 MongoDB \u0130\u015flevsel Fonksiyonlar ve Aggregate Operat\u00f6rleri<\/a> ba\u015fl\u0131kl\u0131 makalemde “$group” operat\u00f6r\u00fc ile nas\u0131l gruplama i\u015fleminin yap\u0131ld\u0131\u011f\u0131na de\u011finmi\u015ftik. Bu i\u00e7eri\u011fimizde ise gruplama i\u015fleminde ekstradan nelerin yap\u0131labilece\u011fini inceleyecek ve tekni\u011fi MongoDB s\u0131n\u0131rlar\u0131nda daha da detayland\u0131raca\u011f\u0131z.<\/p>\n

Makalemizi anla\u015f\u0131labilir k\u0131lmak i\u00e7in birbirleriyle ili\u015fkilendirilmi\u015f “Employee” ve “Order” collectionlar\u0131 \u00fczerinden \u00f6rneklendirmede bulunaca\u011f\u0131z.<\/p>\n\n\n\n\n\n
Employee Collection<\/th>\n Order Collection<\/th>\n<\/tr>\n<\/thead>\n
$\"MongoDB$ <\/a><\/td>\n $\"MongoDB$ <\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\u015eimdi bu collectionlar \u00fczerinde pratiksel a\u00e7\u0131dan g\u00fc\u00e7lenebilmek i\u00e7in \u0131s\u0131nma \u00e7al\u0131\u015fmalar\u0131yla al\u0131\u015ft\u0131rmalar yapal\u0131m.<\/p>\n
\n
\nAl\u0131\u015ft\u0131rma 1<\/strong>
\nT\u00fcm personellerin hangi sat\u0131\u015flar\u0131 yapt\u0131\u011f\u0131n\u0131 listeleyelim<\/em><\/strong><\/p>\n
\r\nrouter.get("\/employeeOrders", (request, response, next) =>\r\n employeeModel.aggregate([\r\n {\r\n $lookup: {\r\n from: "order",\r\n localField: "_id",\r\n foreignField: "employeeId",\r\n as: "orderList"\r\n }\r\n },\r\n {\r\n $unwind: {\r\n path: "$orderList",\r\n preserveNullAndEmptyArrays: true\r\n }\r\n },\r\n {\r\n $group: {\r\n _id: "$name",\r\n orders: {\r\n $push: "$orderList"\r\n }\r\n }\r\n },\r\n {\r\n $project: {\r\n _id: 0,\r\n name: "$_id",\r\n orders: "$orders"\r\n }\r\n }\r\n ])\r\n .then(data => response.json(data))\r\n .catch(error => response.send("Veriler listelenirken beklenmeyen bir hatayla kar\u015f\u0131la\u015f\u0131ld\u0131."))\r\n);\r\n<\/pre>\n
Yukar\u0131da yap\u0131lan \u00e7al\u0131\u015fmada “$group” operat\u00f6r\u00fcne hususi g\u00f6z atarsak e\u011fer;<\/p>\n
\r\n.\r\n.\r\n.\r\n $group: {\r\n _id: "$name",\r\n orders: {\r\n $push: "$orderList"\r\n }\r\n }\r\n.\r\n.\r\n.\r\n<\/pre>\n
“_id” alan\u0131na personelin ad\u0131 atanm\u0131\u015fken, “orders” alan\u0131na kodun \u00f6nceki ad\u0131mlar\u0131nda ili\u015fki sonucu elde edilen “order” collection\u0131ndaki veriler push edilmekte yani dizi olarak verilmektedir.<\/p>\n
Bu i\u015flem neticesinde “$project” operat\u00f6r\u00fc ile “name” alan\u0131na gruplama i\u015flemi netcesinde elde edilen “_id” alan\u0131 verilmekte. Benzer mant\u0131kla “orders” alan\u0131na ise push edilen “orderList” verisi verilerek t\u00fcm sipari\u015fler listelenmektedir.<\/p>\n
Netice olarak;
\n $\"MongoDB$ <\/a><\/p>\n
G\u00f6rd\u00fc\u011f\u00fcn\u00fcz gibi hangi personelin hangi sat\u0131\u015f\u0131 yapt\u0131\u011f\u0131n\u0131 elde etmi\u015f bulunmaktay\u0131z.\n<\/li>\n
\nAl\u0131\u015ft\u0131rma 2<\/strong>
\nHangi personelin ka\u00e7 adet sat\u0131\u015f yapt\u0131\u011f\u0131n\u0131 hesaplayal\u0131m<\/em><\/strong><\/p>\n
\r\nrouter.get("\/employeeOrders", (request, response, next) =>\r\n employeeModel.aggregate([\r\n {\r\n $lookup: {\r\n from: "order",\r\n localField: "_id",\r\n foreignField: "employeeId",\r\n as: "orderList"\r\n }\r\n },\r\n {\r\n $unwind: {\r\n path: "$orderList",\r\n preserveNullAndEmptyArrays: true\r\n }\r\n },\r\n {\r\n $group: {\r\n _id: "$name",\r\n count: { $sum: 1 }\r\n }\r\n }\r\n ])\r\n .then(data => response.json(data))\r\n .catch(error => response.send("Veriler listelenirken beklenmeyen bir hatayla kar\u015f\u0131la\u015f\u0131ld\u0131."))\r\n);\r\n<\/pre>\n
Bu \u015fekilde ili\u015fkilendirme sonucu hangi personelin ka\u00e7 adet sat\u0131\u015f yapt\u0131\u011f\u0131n\u0131 g\u00f6rebiliriz.
\n $\"MongoDB$ <\/a>
\nBurada dikkat edilmesi gereken husus hi\u00e7 sat\u0131\u015f yapmayan personellerin bile sat\u0131\u015f adedi “1” de\u011ferini g\u00f6stermektedir. Bu hatay\u0131 ortadan kald\u0131rabilmek i\u00e7in “$unwind” operat\u00f6r\u00fcndeki “preserveNullAndEmptyArrays” \u00f6zelli\u011fini “false” yapabilirsiniz.\n<\/li>\n
\nAl\u0131\u015ft\u0131rma 3<\/strong>
\nHangi personelin ka\u00e7 adet sat\u0131\u015f yapt\u0131\u011f\u0131n\u0131 daha detayl\u0131 hesaplayal\u0131m<\/em><\/strong>
\nYukar\u0131da yapm\u0131\u015f oldu\u011fumuz \u00e7al\u0131\u015fmay\u0131 daha da detayl\u0131 bir hale getirelim;<\/p>\n
\r\nrouter.get("\/employeeOrders", (request, response, next) =>\r\n employeeModel.aggregate([\r\n {\r\n $lookup: {\r\n from: "order",\r\n localField: "_id",\r\n foreignField: "employeeId",\r\n as: "orderList"\r\n }\r\n },\r\n {\r\n $unwind: {\r\n path: "$orderList",\r\n preserveNullAndEmptyArrays: true\r\n }\r\n },\r\n {\r\n $group: {\r\n _id: {\r\n name: "$name",\r\n surName: "$surName"\r\n },\r\n orders: {\r\n $push: "$orderList"\r\n }\r\n }\r\n },\r\n {\r\n $project: {\r\n _id: 0,\r\n name: "$_id.name",\r\n orderCount: { $size: "$orders" },\r\n orders: "$orders"\r\n }\r\n }\r\n ])\r\n .then(data => response.json(data))\r\n .catch(error => response.send("Veriler listelenirken beklenmeyen bir hatayla kar\u015f\u0131la\u015f\u0131ld\u0131."))\r\n);\r\n<\/pre>\n
Hemen gruplama i\u015flemini incelemek i\u00e7in a\u015fa\u011f\u0131ya alal\u0131m;<\/p>\n
\r\n.\r\n.\r\n.\r\n $group: {\r\n _id: {\r\n name: "$name",\r\n surName: "$surName"\r\n },\r\n orders: {\r\n $push: "$orderList"\r\n }\r\n }\r\n.\r\n.\r\n.\r\n<\/pre>\n
G\u00f6rd\u00fc\u011f\u00fcn\u00fcz gibi “_id” alan\u0131na bu sefer direkt bir de\u011fer vermek yerine object verilmi\u015ftir. \u0130lgili object i\u00e7erisine “name” ve “surName” de\u011ferleri atanm\u0131\u015ft\u0131r. Ayriyetten “orders” alan\u0131na yukar\u0131da ili\u015fkilendirme sonucu elde edilen “orderList” veri k\u00fcmesi atanmaktad\u0131r.<\/p>\n
Bu i\u015flemin devam\u0131nda “$project” operat\u00f6r\u00fcn\u00fcn kullan\u0131m\u0131na g\u00f6z atarsak e\u011fer;<\/p>\n
\r\n.\r\n.\r\n.\r\n $project: {\r\n _id: 0,\r\n name: "$_id.name",\r\n orderCount: { $size: "$orders" },\r\n orders: "$orders"\r\n }\r\n.\r\n.\r\n.\r\n<\/pre>\n
Burada \u00f6zellikle “orderCount” alan\u0131na dikkatinizi \u00e7ekmek istiyorum. “$group” operat\u00f6r\u00fcnden gelen “orders” alan\u0131ndaki koleksiyonun eleman say\u0131s\u0131n\u0131 “$size” operat\u00f6r\u00fcyle hesaplayarak de\u011ferini “orderCount” alan\u0131nda yay\u0131nlamaktay\u0131z.<\/p>\n
$\"MongoDB$ <\/a><\/p>\n
G\u00f6r\u00fcld\u00fc\u011f\u00fc \u00fczere bu \u015fekilde bir \u00e7al\u0131\u015fma sergileyince e\u015fle\u015fmeyen veriler s\u0131f\u0131r olarak g\u00f6sterilmesinden dolay\u0131 daha tutarl\u0131 sonu\u00e7larla kar\u015f\u0131la\u015fm\u0131\u015f bulunmaktay\u0131z.\n<\/li>\n<\/ul>\n
\u0130lgilenenlerin faydalanmas\u0131 dile\u011fiyle…<\/p>\n
Sonraki yaz\u0131lar\u0131mda g\u00f6r\u00fc\u015fmek \u00fczere…
\n\u0130yi \u00e7al\u0131\u015fmalar…<\/p>\n","protected":false},"excerpt":{"rendered":"
Merhaba, \u00d6nceki yaz\u0131lar\u0131mdan NoSQL \u2013 MongoDB \u0130\u015flevsel Fonksiyonlar ve Aggregate Operat\u00f6rleri ba\u015fl\u0131kl\u0131 makalemde “$group” operat\u00f6r\u00fc ile nas\u0131l gruplama i\u015fleminin yap\u0131ld\u0131\u011f\u0131na de\u011finmi\u015ftik. Bu i\u00e7eri\u011fimizde ise gruplama i\u015fleminde ekstradan nelerin yap\u0131labilece\u011fini inceleyecek ve tekni\u011fi MongoDB s\u0131n\u0131rlar\u0131nda...<\/p>\n","protected":false},"author":1,"featured_media":8971,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2539,2145],"tags":[2572,2534,2598],"class_list":["post-9248","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-mongodb","category-node-js","tag-group-operatoru","tag-mongodb","tag-mongodb-group"],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/www.gencayyildiz.com\/blog\/wp-json\/wp\/v2\/posts\/9248","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.gencayyildiz.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.gencayyildiz.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.gencayyildiz.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.gencayyildiz.com\/blog\/wp-json\/wp\/v2\/comments?post=9248"}],"version-history":[{"count":17,"href":"https:\/\/www.gencayyildiz.com\/blog\/wp-json\/wp\/v2\/posts\/9248\/revisions"}],"predecessor-version":[{"id":9270,"href":"https:\/\/www.gencayyildiz.com\/blog\/wp-json\/wp\/v2\/posts\/9248\/revisions\/9270"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.gencayyildiz.com\/blog\/wp-json\/wp\/v2\/media\/8971"}],"wp:attachment":[{"href":"https:\/\/www.gencayyildiz.com\/blog\/wp-json\/wp\/v2\/media?parent=9248"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.gencayyildiz.com\/blog\/wp-json\/wp\/v2\/categories?post=9248"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.gencayyildiz.com\/blog\/wp-json\/wp\/v2\/tags?post=9248"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}