MongoDB-এ $or কোয়েরি বাস্তবায়ন করার পদ্ধতি

MongoDB-এ $or কোয়েরির সিনট্যাক্স নিম্নরূপ:

db.yourCollectionName.find({ $or : [ { "yourFieldName" : "yourValue1" }, {"yourFieldName":"yourValue2"},...........N ] } ).pretty();

কonception বুঝতে ডকুমেন্টসহ একটি কলেকশন তৈরি করি। ডকুমেন্টসহ কলেকশন তৈরির কোয়েরি নিম্নরূপ:

> db.orDemo.insertOne({"UserName":"Larry","UserAge":23}); { "acknowledged" : true, "insertedId" : ObjectId("5c9491fd4cf1f7a64fa4df4c") } > db.orDemo.insertOne({"UserName":"David","UserAge":21}); { "acknowledged" : true, "insertedId" : ObjectId("5c9492074cf1f7a64fa4df4d") } > db.orDemo.insertOne({"UserName":"Mike","UserAge":25}); { "acknowledged" : true, "insertedId" : ObjectId("5c94920e4cf1f7a64fa4df4e") } > db.orDemo.insertOne({"UserName":"Sam","UserAge":20}); { "acknowledged" : true, "insertedId" : ObjectId("5c9492144cf1f7a64fa4df4f") } > db.orDemo.insertOne({"UserName":"Carol","UserAge":24}); { "acknowledged" : true, "insertedId" : ObjectId("5c94921d4cf1f7a64fa4df50") } > db.orDemo.insertOne({"UserName":"Bob","UserAge":22}); { "acknowledged" : true, "insertedId" : ObjectId("5c94922c4cf1f7a64fa4df51") }

find() মেথড ব্যবহার করে কলেকশন থেকে সব ডকুমেন্ট প্রদর্শন করি। কোয়েরিটি নিম্নরূপ:

> db.orDemo.find().pretty();

নিচের আউটপুট:

{ "_id" : ObjectId("5c9491fd4cf1f7a64fa4df4c"), "UserName" : "Larry", "UserAge" : 23 } { "_id" : ObjectId("5c9492074cf1f7a64fa4df4d"), "UserName" : "David", "UserAge" : 21 } { "_id" : ObjectId("5c94920e4cf1f7a64fa4df4e"), "UserName" : "Mike", "UserAge" : 25 } { "_id" : ObjectId("5c9492144cf1f7a64fa4df4f"), "UserName" : "Sam", "UserAge" : 20 } { "_id" : ObjectId("5c94921d4cf1f7a64fa4df50"), "UserName" : "Carol", "UserAge" : 24 } { "_id" : ObjectId("5c94922c4cf1f7a64fa4df51"), "UserName" : "Bob", "UserAge" : 22 }

$or কোয়েরির উদাহরণ:

> db.orDemo.find({ $or : [ { "UserName" : "Carol" }, {"UserName":"Larry"} ] } ).pretty();

নিচের আউটপুট:

{ "_id" : ObjectId("5c9491fd4cf1f7a64fa4df4c"), "UserName" : "Larry", "UserAge" : 23 } { "_id" : ObjectId("5c94921d4cf1f7a64fa4df50"), "UserName" : "Carol", "UserAge" : 24 }