Scala對MongoDB的增刪改查操作

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　　　　原文鏈接： Scala對MongoDB的增刪改查操作 轉載請注明出處！

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依賴環境：jdk1.8、Scala 2.12、idea

　　　　mongodb Driver:3.1.1。注意，mongo for scala的驅動涉及多個jar(如下圖)，依賴於mongo-java-driver.jar

　　　　這里使用的sbt管理依賴,直接在build.sbt中添加依賴：libraryDependencies += "org.mongodb" %% "casbah" % "3.1.1"（強烈建議使用該方法添加依賴）

一、創建數據庫連接

A：不需要用戶名和密碼直接獲取MongoDB。

  //  無權限驗證連接
  def createDatabase(url: String, port: Int, dbName: String): MongoDB = {
    MongoClient(url, port).getDB(dbName)
  }

 

 　　這里需要注意一下，在導入的jar包存在兩個MongoClient類，一個來自於mongo-java-driver.jar的com.mongodb.MongoClient，另一個來自於casbah-core_2.12:3.1.1.jar的com.mongodb.casbah.MongoClient.前者是用於java調用，Scala使用后者!!!

因此導入包的時候要注意為：import com.mongodb.casbah.MongoClient

 

B:通過權限驗證進行連接

 //驗證連接權限
  def createDatabase(url: String, port: Int, dbName: String, loginName: String, password: String): MongoDB = {
    var server = new ServerAddress(url, port)
    //注意：MongoCredential中有6種創建連接方式，這里使用MONGODB_CR機制進行連接。如果選擇錯誤則會發生權限驗證失敗
    var credentials = MongoCredential.createCredential(loginName, dbName, password.toCharArray)
    var mongoClient = MongoClient(server, List(credentials))
    mongoClient.getDB(dbName)
  }

 

這里需要注意的是MongoCredential.createCredential(),在MongoCredential中存在着六種認證機制，這里使用createCredential()進行創建，使用錯誤則將會驗證失敗

com.mongodb.MongoSecurityException: Exception authenticating

Caused by: com.mongodb.MongoCommandException: Command failed with error 18: 'auth failed' on server localhost:27017. The full response is { "ok" : 0.0, "errmsg" : "auth failed", "code" : 18, "codeName" : "AuthenticationFailed" }

該方法注釋如下：

/**
 * Creates a MongoCredential instance with an unspecified mechanism. The client will negotiate the best mechanism
 * based on the version of the server that the client is authenticating to. If the server version is 2.8 or higher,
 * the driver will authenticate using the SCRAM-SHA-1 mechanism. Otherwise, the driver will authenticate using the
 * MONGODB_CR mechanism.
 *
 * @param userName the user name
 * @param database the database where the user is defined
 * @param password the user's password
 */

 二、數據添加

  def testInsert(): Unit = {
    for (i <- 1 to 100)
      collection.insert(MongoDBObject("name" -> "Jack%d".format(i), "email" -> "[e-mail]".format(i), "age" -> i % 25, "birthDay" -> new SimpleDateFormat("yyyy-MM-dd").parse("2016-03-25")))
  }

 這里的collection是在下面創建的：

 var collection= createDatabase("localhost", 27017, "mytest", "user", "123456").getCollection("user")

 

 在進行數據插入的時候，如果不存在該collection則會自動創建（這里是user），如果document中不包含“_id”字段則會自動添加該字段。

DBCollection中存在一個save方法，該save方法區別於insert的地方在於當“_id”存在於集合中，save將會進行更新數據，而insert不會進行任何操作

 根據需要選擇適合的數據插入函數

存儲之后數據如下：

 { "_id" : { "$oid" : "592ad4be45aefd09f4867f1e"} , "name" : "Jack86" , "email" : "[e-mail]" , "age" : 11 , "birthDay" : { "$date" : "2016-03-24T16:00:00.000Z"}}
 { "_id" : { "$oid" : "592ad4be45aefd09f4867f1f"} , "name" : "Jack87" , "email" : "[e-mail]" , "age" : 12 , "birthDay" : { "$date" : "2016-03-24T16:00:00.000Z"}}
{ "_id" : { "$oid" : "592ad4be45aefd09f4867f20"} , "name" : "Jack88" , "email" : "[e-mail]" , "age" : 13 , "birthDay" : { "$date" : "2016-03-24T16:00:00.000Z"}}
{ "_id" : { "$oid" : "592ad4be45aefd09f4867f21"} , "name" : "Jack89" , "email" : "[e-mail]" , "age" : 14 , "birthDay" : { "$date" : "2016-03-24T16:00:00.000Z"}}

三、數據更新修改

A：更新方式一

  def testUpdate(): Unit = {
    var query = MongoDBObject("name" -> "user1", "email" -> "[e-mail]")
    var value = MongoDBObject("name" -> "user1", "email" -> "[e-mail]123456")
    println("=========更新之前============")
    var query02 = MongoDBObject("name" -> "user1")
    collection.find(query02).forEach(x => println(x))
//    query:根據此條件進行查詢  value：把查詢出來結果集的第一條數據設置為value
    collection.update(query,value)
    println("=========更新之后============")
    collection.find(query02).forEach(x => println(x))
  }

 

運行結果如下：（注意這里只更新了一條記錄，並不是把所有符合結果的數據都進行更新）

B：更新方式二

  def testUpdate02(): Unit = {
    var query = MongoDBObject("name" -> "user1", "email" -> "[e-mail]123456")
    var value = new BasicDBObject("$set", new BasicDBObject("email", "[e-mail]"))
    //     var value = MongoDBObject("$set",MongoDBObject("name" -> "user1", "email" -> "[e-mail]123"))
    println("=========更新之前============")
    var query02 = MongoDBObject("name" -> "user1")
    collection.find(query02).forEach(x => println(x))
    collection.update(query, value,true, true)
    println("=========更新之后============")
    collection.find(query02).forEach(x => println(x))
  }

 

 注意該方法：collection.update(query, value,true, true)。

　　　　第三個參數：when true, inserts a document if no document matches the update query criteria

　　　　第四個參數：when true, updates all documents in the collection that match the update query criteria, otherwise only updates one【當該值為true時，則更新所有的結果集數據，不過前提是value必須使用“$XXX”模式進行定義】。源碼如下：

 

四、數據查詢（建議看下這篇文章：MongoDB學習筆記(查詢)）

  def testSelect(): Unit ={
    println("=========查詢所有數據===================")
    collection.find().forEach(x => println(x))
    println("=========查詢name = “user1”  同時email=“[e-mail]”===================")
    collection.find(MongoDBObject("name" -> "user1", "email" -> "[e-mail]")).limit(3).forEach(x => println(x))
    //    注意此處不能使用put添加其他查詢條件，因為put返回的是HashMap,此處應該使用append進行添加查詢條件
    //  var query = new BasicDBObject("name",new BasicDBObject("$in",("user145","user155"))).put("qty",new BasicDBObject("$in",(25.0,105.0)))  該方法錯誤
    //    查詢條件為： (name in ("user145","user155")) && (qty in (25.0,105.0))
    println("=========查詢 (name in (\"user145\",\"user155\")) && (qty in (25.0,105.0))===================")
    var query = new BasicDBObject("name", new BasicDBObject("$in", ("user145", "user155"))).append("qty", new BasicDBObject("$in", (25.0, 105.0)))
    collection.find(query).forEach(x => println(x))
    println("=========查詢 start >= 10 && end<= 80 的數據===================")
    var query02 = new BasicDBObject("start", new BasicDBObject("$gte", 10)).append("end", new BasicDBObject("$lte", 80))
    collection.find(query02).forEach(x => println(x))
  }

 

 查詢結果如下：

五、數據刪除

數據刪除主要是構建一個查詢條件，把符合該條件的所有數據都進行刪除

  def testDelete(): Unit ={
    var query = MongoDBObject("name" -> "user1", "email" -> "[e-mail]")
    println("=========刪除之前============")
    collection.find(query).forEach(x => println(x))
    //該參數只是一個查詢條件，符合該條件的所有集合都將被刪除。重點在於如何構建query
    collection.remove(query)
    println("=========刪除之前============")
    collection.find(query).forEach(x => println(x))
  }

  執行結果如下：

=========刪除之前============

{ "_id" : { "$oid" : "592a0c8345aefd1d404c3ed9"} , "name" : "user1" , "email" : "[e-mail]"}
{ "_id" : { "$oid" : "592a0c8345aefd1d404c3eda"} , "name" : "user1" , "email" : "[e-mail]"}
{ "_id" : { "$oid" : "592a0c9845aefd0dfc2a1e21"} , "name" : "user1" , "email" : "[e-mail]"}
{ "_id" : { "$oid" : "592a0c9845aefd0dfc2a1e23"} , "name" : "user1" , "email" : "[e-mail]"}
{ "_id" : { "$oid" : "592a740f434a43d3b1529d0e"} , "name" : "user1" , "email" : "[e-mail]"}
=========刪除之后============

remove方法有如下四種，根據具體情況選取合適的方法：

附測試源碼：

package tool

import java.text.SimpleDateFormat
import java.util
import java.util.Date

import com.mongodb.casbah.commons.MongoDBObject
import com.mongodb.{BasicDBObject, DBCollection, ServerAddress}
import com.mongodb.casbah.{MongoClient, MongoCredential, MongoDB}
import com.mongodb.client.model.Filters
import org.joda.time.DateTime

/**
  * Created with IntelliJ IDEA.
  * Description:
  * User: Perkins Zhu
  * Date: 2017-05-28
  * Time: 19:33
  */
object MongoTool {
  def main(args: Array[String]): Unit = {
//        testInsert
//    testUpdate02
//    testSelect
  testDelete
  }
  def testDelete(): Unit ={
    var query = MongoDBObject("name" -> "user1", "email" -> "[e-mail]")
    println("=========刪除之前============")
    collection.find(query).forEach(x => println(x))
    //該參數只是一個查詢條件，符合該條件的所有集合都將被刪除
    collection.remove(query)
    collection.findAndRemove()
    println("=========刪除之前============")
    collection.find(query).forEach(x => println(x))
  }


  def testUpdate01(): Unit = {
    var query = MongoDBObject("name" -> "user1", "email" -> "[e-mail]")
    var value = MongoDBObject("name" -> "user1", "email" -> "[e-mail]123456")
    println("=========更新之前============")
    var query02 = MongoDBObject("name" -> "user1")
    collection.find(query02).forEach(x => println(x))
//    query:根據此條件進行查詢  value：把查詢出來結果集的第一條數據設置為value
    collection.update(query,value)
    println("=========更新之后============")
    collection.find(query02).forEach(x => println(x))
  }

  def testUpdate02(): Unit = {
    var query = MongoDBObject("name" -> "user1", "email" -> "[e-mail]123456")
    var value = new BasicDBObject("$set", new BasicDBObject("email", "[e-mail]"))
    //     var value = MongoDBObject("$set",MongoDBObject("name" -> "user1", "email" -> "[e-mail]123"))
    println("=========更新之前============")
    var query02 = MongoDBObject("name" -> "user1")
    collection.find(query02).forEach(x => println(x))
    collection.update(query, value,true, true)
    println("=========更新之后============")
    collection.find(query02).forEach(x => println(x))
  }

  def testSelect(): Unit ={
    println("=========查詢所有數據===================")
    collection.find().forEach(x => println(x))
    println("=========查詢name = “user1”  同時email=“[e-mail]”===================")
    collection.find(MongoDBObject("name" -> "user1", "email" -> "[e-mail]")).limit(3).forEach(x => println(x))
    //    注意此處不能使用put添加其他查詢條件，因為put返回的是HashMap,此處應該使用append進行添加查詢條件
    //  var query = new BasicDBObject("name",new BasicDBObject("$in",("user145","user155"))).put("qty",new BasicDBObject("$in",(25.0,105.0)))  該方法錯誤
    //    查詢條件為： (name in ("user145","user155")) && (qty in (25.0,105.0))
    println("=========查詢 (name in (\"user145\",\"user155\")) && (qty in (25.0,105.0))===================")
    var query = new BasicDBObject("name", new BasicDBObject("$in", ("user145", "user155"))).append("qty", new BasicDBObject("$in", (25.0, 105.0)))
    collection.find(query).forEach(x => println(x))
    println("=========查詢 start >= 10 && end<= 80 的數據===================")
    var query02 = new BasicDBObject("start", new BasicDBObject("$gte", 10)).append("end", new BasicDBObject("$lte", 80))
    collection.find(query02).forEach(x => println(x))
  }

  def testInsert(): Unit = {
    for (i <- 1 to 100)
//      注意與saved的區別
      collection.insert(MongoDBObject("name" -> "Jack%d".format(i), "email" -> "[e-mail]".format(i), "age" -> i % 25, "birthDay" -> new SimpleDateFormat("yyyy-MM-dd").parse("2016-03-25")))
  }

  var collection = createDatabase("localhost", 27017, "mytest", "user", "123456").getCollection("user")

  //驗證連接權限
  def createDatabase(url: String, port: Int, dbName: String, loginName: String, password: String): MongoDB = {
    var server = new ServerAddress(url, port)
    //注意：MongoCredential中有6種創建連接方式，這里使用MONGODB_CR機制進行連接。如果選擇錯誤則會發生權限驗證失敗
    var credentials = MongoCredential.createCredential(loginName, dbName, password.toCharArray)
    var mongoClient = MongoClient(server, List(credentials))
    mongoClient.getDB(dbName)
  }

  //  無權限驗證連接
  def createDatabase(url: String, port: Int, dbName: String): MongoDB = {
    MongoClient(url, port).getDB(dbName)
  }
}

 

 

--end