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<div class="post-text" itemprop="text"> <p>Using a file clearTestData.php to remove data from a collection in my database. It includes a query that seems to be showing the collection is empty at the end. When I check with list.php however which has the same query, nothing is deleted. Complete mongo noob here, server provided by unviersity. Testing both by accessing through browser "server..../clearTestData.php".</p> <p>ClearTestData.php:</p> <pre><code>&lt;?php // connect to mongodb $user = "muntean"; require '/var/composer/vendor/autoload.php'; $manager = new MongoDB\Driver\Manager("mongodb://localhost:27017"); echo "Connection to database successfully. "; $collection = new MongoDB\Collection($manager, $user, 'testData'); echo "deleting contents of collection user.testData. "; // now remove the document $collection-&gt;remove(array("node"=&gt;"xyzWXX"),false); // db.testData.deleteMany({}); echo "Documents deleted successfully."; $filter = []; $options = []; $query = new MongoDB\Driver\Query($filter, $options); $cursor = $manager-&gt;executeQuery("$user.testData", $query); print("The contents of the collection $user.testData are: "); print_r($cursor-&gt;toArray()); ?&gt; </code></pre> <p>list.php:</p> <pre><code>&lt;html&gt;&lt;body&gt; &lt;?php $user = "muntean"; require '/var/composer/vendor/autoload.php'; $manager = new MongoDB\Driver\Manager("mongodb://localhost:27017"); $collection = new MongoDB\Collection($manager, $user, 'testData'); $filter = []; $options = []; $query = new MongoDB\Driver\Query($filter, $options); $cursor = $manager-&gt;executeQuery("$user.testData", $query); print("The contents of the collection $user.testData are:"); print_r($cursor-&gt;toArray()); ?&gt; </code></pre> <p>Output list in browser:</p> <p>The contents of the collection muntean.testData are:Array ( [0] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5bd1c6871c37212c6c218b42 ) [node] =&gt; N13 [data] =&gt; 10 ) [1] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5bd1cad41c37212c66789d33 ) [node] =&gt; N13 [data] =&gt; 10 ) [2] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5bd1cb861c37212c66789d34 ) [node] =&gt; N13 [data] =&gt; 10 ) [3] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5bd718621c3721165402d2f2 ) [node] =&gt; N13 [data] =&gt; 10 ) [4] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5bd7221f1c372116132eaf82 ) [node] =&gt; N13 [data] =&gt; 10 ) [5] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5bd722241c372116125a1fc2 ) [node] =&gt; N13 [data] =&gt; 10 ) [6] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5bd722581c3721165402d2f3 ) [node] =&gt; N13 [data] =&gt; 10 ) [7] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5be304c21c3721252357e882 ) [node] =&gt; N13 [data] =&gt; 10 ) [8] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5be308b71c372124f456ccb2 ) [node] =&gt; N13 [data] =&gt; 10 ) [9] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5be340901c372124f456ccb3 ) [node] =&gt; N13 [data] =&gt; 10 ) [10] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5be373421c372124f10feee2 ) [node] =&gt; N13 [data] =&gt; 10 ) [11] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5c6d6a651c372113771565f2 ) [node] =&gt; N13 [data] =&gt; 10 ) [12] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5c6d6a8a1c3721137b0653b2 ) [node] =&gt; N13 [data] =&gt; 10 ) [13] =&gt; stdClass Object ( [_id] =&gt; MongoDB\BSON\ObjectId Object ( [oid] =&gt; 5c6d6af51c372113791c77c2 ) [node] =&gt; N13 [data] =&gt; 53.374057769775-6.6027770042419 ) )</p> <p>output clear in browser:</p> <p>Connection to database successfully. deleting contents of collection user.testData.</p> </div>


mongodb现有集合test, 表的数据量大概为500w 集合中的文档为以下格式: { "_id" : "15998854009", "coordinate" : { "longitude" : 120.0123, "latitude" : 30.0254 }, "uploadtime" : "20160525090100", "bookmark" : 1 } 现需要改造集合的结构,增加一个性别属性:sex, sex的值不固定 改造后的文档格式要求为: { "_id" : "42000308329", "coordinate" : { "longitude" : 120.073094, "latitude" : 30.28031 }, "uploadtime" : "20160530150101", "bookmark" : 1, "sex" : 1 } 目前的方案是将原有数据导出,并对原有数据进行改造,改造成要求的格式,并通过代码逐条更新mongodb中的数据。 请问是否有更好的方案?mongodb是否提供批量更新的工具操作


<div class="post-text" itemprop="text"> <p><strong>I have a mongodb collection like</strong></p> <pre><code>{ "_id" : 57, "value" : { "user" : [ { "fk_status_id" : "0", "firstname" : "Ajith", "lastname" : "S", "city" : "known", "State" :"kerala", "location" : { "lat" : 34.123456, "lon" : -95.123456 }, } ], }} </code></pre> <p><strong>with millions of documents</strong></p> <p><strong>I want to alter the table structure like this</strong></p> <pre><code>{ "_id" : 58, "user" : [ { "fk_status_id" : "0", "firstname" : "Ajith", "lastname" : "S", "city" : "known", "State" :"kerala", "location" : { "lat" : 34.123456, "lon" : -95.123456 }, } ]} </code></pre> <p><strong>I mean ,I want to omit the 'value{}' from this structure.</strong></p> <ul> <li>The data should come outside 'values'. Please resolve my problem.</li> </ul> </div>

GOlang mongodb从集合中删除所有项目

<div class="post-text" itemprop="text"> <p>How to remove all items from collection stored in mongodb using GO lang? </p> <p>In mongo console I can use:</p> <pre><code>db.mycollection.remove({}) </code></pre> <p>where empty brackets {} mean all document pattern.</p> <p>In GO lang (I use "" and "") there are methods:</p> <pre><code>sess.DB("mydb").C("mycollection").Remove(...) or sess.DB("mydb").C("mycollection").RemoveAll(...) </code></pre> <p>but both of them needs parameter that implements selector. For example selector can be a bson map</p> <pre><code>bson.M{"id": id} </code></pre> <p>but I want to remove all elements, not a particular one.</p> </div>


<div class="post-text" itemprop="text"> <p>Assume $db is a made mongoDB connection with php.</p> <p>There is no collection exists yet.</p> <p>I inserted one data</p> <pre><code>$db-&gt;board_name-&gt;board-&gt;article-&gt;insert(array("title"=&gt;"example")); </code></pre> <p>this is equivalent to </p> <pre><code>db.board_name.board.article.insert({"title":"example"}) </code></pre> <p>the problem is it inserts not the </p> <blockquote> <p>db.board_name.board</p> </blockquote> <p>structure but</p> <p>just simply inserts "db.board_name.board.article" &lt;--- these three as a string.</p> <p>Does it just demonstrates like a combined string for now </p> <p>because there is no other elements after "board_name"?</p> <p>What if I add more things right after "board_name" like </p> <pre><code>db.board_name.rank.insert({"something":"thing"}); </code></pre> <p>Does mongoDB smartly recognize "rank" collection as part of "board_name" in that case?</p> <p>or simply creates other collection with "db.board_name.rank"?</p> </div>


<div class="post-text" itemprop="text"> <p>I have these 3 mongoDB collections :</p> <p>client_results</p> <pre><code>[ 'resultId':1, 'clientId':'client00', ], [ 'resultId':2, 'clientId':'client00', ], </code></pre> <p>results</p> <pre><code>[ 'id':1, 'siteID':5 ], [ 'id':2, 'siteID':6 ] </code></pre> <p>sites</p> <pre><code>[ 'id':5, 'language':'ar' ], [ 'id':6, 'language':'en' ] </code></pre> <p>how I can get client_results where = 'en' ? in MYSQL query will like this :</p> <pre><code>select, cr.clientId from client_results cr left join results r on = cr.resultId left join site s on = r.siteID where s.language = 'en'; </code></pre> <p>but in mongoDB how I can make this query ?</p> <p>thanks</p> </div>


<div class="post-text" itemprop="text"> <p>The following collection contains the ticks for the diverse exchange symbols (in this case <code>BTCUSD</code> and <code>BTCEUR</code>):</p> <pre><code>{ "_id" : ObjectId("5a08d2b956df9b2302759d1a"), "symbol" : "BTCUSD", "time" : ISODate("2013-04-13T00:00:00Z"), "open" : 112, "close" : 91.1, "high" : 130, "low" : 81.12, "volume" : 23866.6770456 } { "_id" : ObjectId("5a08d2b956df9b2302759d1c"), "symbol" : "BTCUSD", "time" : ISODate("2013-04-14T00:00:00Z"), "open" : 91.1, "close" : 90.171, "high" : 109, "low" : 20, "volume" : 16437.2196645 } { "_id" : ObjectId("5a08d2b956df9b2302759d1e"), "symbol" : "BTCEUR", "time" : ISODate("2013-04-15T00:00:00Z"), "open" : 89.86, "close" : 83.302, "high" : 104, "low" : 71.497, "volume" : 16393.12856398 } { "_id" : ObjectId("5a08d2b956df9b2302759d20"), "symbol" : "BTCEUR", "time" : ISODate("2013-04-16T00:00:00Z"), "open" : 84.27, "close" : 67.588, "high" : 84.48, "low" : 0.01, "volume" : 26092.5432296 } </code></pre> <p>How do I get the list of symbols actually present in the collection in <code>Go</code>? For instance, the result I'm looking for is:</p> <pre><code>{ "BTCUSD", "BTCEUR" } </code></pre> <p>This would let me retrieve the latest tick values from the exchange service without having to store somewhere the symbols I'm interested in.</p> <p>From the <code>mongo</code> shell I've tried this...</p> <pre><code>db.candles.aggregate({$group: {_id:"$symbol"}}) </code></pre> <p>... and here is the result:</p> <pre><code>{ "_id" : "BTCUSD" } { "_id" : "BTCEUR" } </code></pre> <p>What is the equivalent in <code>Go</code> using <code>mgo</code>? Is it possible to just get an array of symbols instead of a collection of <code>"_id" : "value"</code> pairs?</p> </div>


<div class="post-text" itemprop="text"> <p>I tried the following code for selecting all the records from mongodb collection.But only last inserted record will come.</p> <pre><code>&lt;?php $m=new MongoClient(); $db=$m-&gt;trip; if($_SERVER['REQUEST_METHOD']=="POST") { $userId=$_POST['userId']; $param=explode(",",$userId); $collection=$db-&gt;chat; $record=$collection-&gt;find(array("userId"=&gt;$userId)); if($record) { foreach($record as $rec) { $json=array("msg"=&gt;$rec); } } else { $json=array("msg"=&gt;"No Records"); } } else { $json=array("msg"=&gt;"Request Method is Not Accespted"); } //output header header('Content-type:application/json'); echo json_encode($json); </code></pre> <p>?&gt;</p> <p>But only one record will come please help me</p> </div>


<div class="post-text" itemprop="text"> <p>I have one collection (CollectionA) . in this collection there are data of more experiment.</p> <p>I want create one collection for each experiment: Collection1, Collection2 ...</p> <p>There is a mode? without losing data?</p> <p>ps. I can interfacing MongoDB with php</p> <hr> <p>Add information:</p> <p>I have a Collection with MANY MANY data of experiment (experimentA,ExperimentB,...).</p> <p>I want split this collection in more collection one for each Experiment.</p> <p>(a kind of partition)</p> <hr> <pre><code>Collection NAME = testCollection </code></pre> <p>in this Collection there is "experiment" field (ex. ExperimentA , ExperimentB , ...)</p> <p>COLLECTION OUTPUT REQUIRED : </p> <pre><code>testCollection_ExperimentA testCollection_ExperimentB </code></pre> <p>Need more information? </p> </div>


<div class="post-text" itemprop="text"> <p>I have inserted data into mongodb in the following way</p> <pre><code> { "_id" : ObjectId("5c80e9cc3bf127cfc80ba5dc"), "resp" : [ { "name" : "by", "gender" : "synced", "age" : "response", "hobby" : "submitted", "mobile" : "revision" }, { "name" : "byoooooo", "gender" : "sytewed", "age" : "se", "hobby" : "subed", "mobile" : "revissaaon" } ] } </code></pre> <p>Using this method</p> <pre><code>func (d *CollectDAO) Insert(responses []*models.FormData) error { resp := models.Responses{ Data: responses, } err := db.C(formsCollection).Insert(resp) return err } </code></pre> <p>This is the struct used in the insert method</p> <pre><code>type FormData struct { Name string `csv:"name" json:"name" bson:"name"` Gender string `csv:"gender" json:"gender" bson:"gender"` Age string `csv:"age" json:"age" bson:"age"` Hobby string `csv:"hobby" json:"hobby" bson:"hobby"` MobileNo string `csv:"mobile" json:"mobile" bson:"mobile"` } </code></pre> <p>The handler reads sample csv data from a file. This is the csv data</p> <pre><code>name,gender,age,hobby,mobile by,synced,response,submitted,revision byoooooo,sytewed,se,subed,revissaaon </code></pre> <p>And then inserts that into mongo</p> <p>When querying all the documents of my collection I get an empty response</p> <pre><code>func (d *CollectDAO) FindAll() (models.Responses, error) { var responses []models.Responses err := db.C(formsCollection).Find(nil).All(&amp;responses) if err != nil { log.Fatal(err) } log.Printf("all docs %v ", responses) return responses, err } </code></pre> <p>When I try to log the value of the struct I get an empty struct. This is the responses struct that I am using at the end to put the slice of response in.</p> <pre><code>type Responses struct { Data []*FormData `json:"response"` } </code></pre> <p>What am I doing wrong? I just need to implement a handler that will return all the data in a collection as a struct.</p> <p>On the client side I get this error</p> <pre><code>unexpected end of JSON input {ObjectIdHex("") []} </code></pre> </div>


<div class="post-text" itemprop="text"> <p>How can I rename a collection in mongodb sharding? Because I tried in my production server, its thrown the following error just for your references. </p> <p>My Requirement we have to add few more fields with value on existing collection. But In production we can't able to disrupt the traffic based collection and anytime request comes from member simultaneously. So we have planned to populate the entire records from sql to mongo in another collection and then rename the collection and make it as production. its our plan. But we cant able to take it further. Following error we got it.</p> <pre><code>db.clientdetails.renameCollection( "clientdetails_bkup" ); { "assertion" : "You can't rename a sharded collection", "assertionCode" : 13138, "errmsg" : "db assertion failure", "ok" : 0 } </code></pre> <p>If not possible in mongodb sharding, please share your suggestion or alternative way we can solve this issue.</p> <p>Please suggest what we have to take it further?.</p> </div>

Go MongoDB(mgo)-不释放封闭的连接

<div class="post-text" itemprop="text"> <p>My MongoDB database has a fast-growing amount of active connections.</p> <p>I wrote a code to test how connection creation/closing flow works. This code sums up how I use the <code>mgo</code> library in my project.</p> <pre><code>package main import ( "time" "fmt" "" ) func main() { // No connections // db.serverStatus().connections.current = 6 mongoSession := connectMGO("localhost", "27017", "admin") // 1 new connection created //db.serverStatus().connections.current = 7 produceDataMGO(mongoSession) produceDataMGO(mongoSession) produceDataMGO(mongoSession) produceDataMGO(mongoSession) // 4 new connections created and closed // db.serverStatus().connections.current = 7 go produceDataMGO(mongoSession) go produceDataMGO(mongoSession) go produceDataMGO(mongoSession) go produceDataMGO(mongoSession) // 4 new connections created and closed concurrently // db.serverStatus().connections.current = 10 time.Sleep(time.Hour * 24) // wait any amount of time // db.serverStatus().connections.current = 10 } func connectMGO(host, port, dbName string) *mgo.Session { session, _ := mgo.DialWithInfo(&amp;mgo.DialInfo{ Addrs: []string{fmt.Sprintf("%s:%s", host, port)}, Timeout: 10 * time.Second, Database: dbName, Username: "", Password: "", }) return session } func produceDataMGO(conn *mgo.Session) { dbConn := conn.Copy() dbConn.DB("").C("test").Insert("") dbConn.Close() } </code></pre> <p>I detected a pretty weird thing that I don't understand. Behaviour is somehow different depending on how we create new connections (sync/async). </p> <p>If we create connection synchronously - mongo closes this new connection immediately after calling <code>.Close()</code> method.</p> <p>If we create connection asynchronously - mongo keeps this new connection alive even after calling <code>.Close()</code> method.</p> <p><strike></strike></p> <ol> <li><p>Why is it so?</p></li> <li><p>Is there any other way to force-close connection socket?</p></li> <li><p>Will it auto-close these open connections after a certain amount of time?</p></li> <li>Is there any way to set a limit for the amount of connections MongoDB can expand its pool to?</li> <li>Is there any way to setup an auto-truncate after a certain amount of time without high load?</li> </ol> </div>


对A,B两个集合同时创建两组复合索引,索引字段都才4个,创建成功后查询速度比原来快多了。过一天后查询看发现A集合又慢了,发现A集合的复合索引没有了,B集合的索引还在。(A集合数据比较大一大) 给A重新创建了几次索引,都是过段时间索引就自动消失了。要重新创建。求解啊


<div class="post-text" itemprop="text"> <p>I have a collection where all form data is stored, each form with a different structure, but some forms with overlapping field names. I love mongo for the ease it proves here, allowing me to sort and aggregate totally different data based upon a few small common factors.</p> <p>Now, for the UI, I need a list of all possible fields in the database so a user can choose which fields to view. I can't seem to find any mongo anything to return a list of fields, except for indexes. </p> <p>How would I go about this?</p> </div>




<div class="post-text" itemprop="text"> <p>I have a return object coming from instagram. I am trying to skate the entire build DB table structure process, I understand Mongo is the ideal DB to use for this task.</p> <p>I am using the regular instagram libraries <a href="" rel="nofollow"></a> and my test code runs without error. I don have the PhP PECL mongo libraries installed, I should be good to go.</p> <pre><code>session_start(); require 'vendor/autoload.php'; use MetzWeb\Instagram\Instagram; $instagram = new Instagram(array( 'apiKey' =&gt; 'xxx', 'apiSecret' =&gt; 'xxx', 'apiCallback' =&gt; '' )); $accessToken = $instagram-&gt;getAccessToken(); $_SESSION['InstagramAccessToken'] = $accessToken; $instagram-&gt;setAccessToken($_SESSION['InstagramAccessToken']); $popular = $instagram-&gt;getPopularMedia(); // After getting the response, let's iterate the payload var_dump($popular); </code></pre> <p>added just now:</p> <pre><code>$conn = new MongoClient('mongodb://localhost/?w=1'); $db = $conn-&gt;instagram; // access collection $collection = $db-&gt;instagram1; $collection-&gt;insert($popular); </code></pre> <p>How would I construct a PDO query to 'autobuild' the table structure just like the JSON object at reply from my request?</p> <p><a href="" rel="nofollow">instagram JSON object</a></p> <p><a href="" rel="nofollow">Repaste of object. Most got cut off due to size</a></p> <p>Update: I tried to insert straight into a collection, I get no error but the DB is still the same size</p> <blockquote> <p>show dbs Data 0.078GB admin (empty) instagram 0.078GB local 0.078GB test 0.078GB week1 (empty)</p> </blockquote> </div>


<div class="post-text" itemprop="text"> <div class="question-status question-originals-of-duplicate"> <p>This question already has an answer here:</p> <ul> <li> <a href="/questions/44779549/how-to-match-on-joined-collections-using-laravel-and-mongodb" dir="ltr">How to Match on Joined Collections Using Laravel and MongoDB?</a> <span class="question-originals-answer-count"> 1 answer </span> </li> <li> <a href="/questions/44948677/how-to-join-to-two-additional-collections-with-conditions" dir="ltr">How to join to two additional collections with conditions</a> <span class="question-originals-answer-count"> 1 answer </span> </li> <li> <a href="/questions/45724785/aggregate-lookup-total-size-of-documents-in-matching-pipeline-exceeds-maximum-d" dir="ltr">Aggregate $lookup Total size of documents in matching pipeline exceeds maximum document size</a> <span class="question-originals-answer-count"> 1 answer </span> </li> </ul> </div> <p>I have 2 collections in mongoDB namely <code>product</code> and <code>author</code> . Now the <code>product</code> collection has an object called the <code>detail</code> which has the <code>title</code> and other details whereas the <code>author</code> table has details regarding the <code>author</code> . Now i am trying to make a search that finds both <code>title</code> and <code>author</code> .. For eg: if the <code>title</code> is matched the <code>details</code> of that <code>product</code> should be listed and if the <code>author</code> is matched then again the <code>details</code> of that <code>product</code> should be shown. The <code>author_id</code> is a <code>foreign_key</code> in the <code>product</code> collection and the <code>_id</code> is a primary key in the author collection.</p> <p>Below is my collection</p> <p>The <code>Product</code> Collection</p> <pre><code>{ "_id" : ObjectId("5af2bd44a003533a8abf4e56"), "product_type_id" : "5ae834807ae0d9538e45ab45", "date_added" : "2018-03-12 12-3-54", "status" : 1, "detail" : { "title" : "The random title", "author_id" : "5af2c401a003533a8abf4e57", "test_id" : 12345, "description" : "I have a mongoDB collection with f rows", "mrp" : 200, "binding" : "sd", "language" : "English", "isbn" : NumberLong("9788700631625"), "isbn_10" : 747532745, "ean" : 897655, "pages" : 200 } } </code></pre> <p>This is the <code>author</code> collection</p> <pre><code>{ "_id" : ObjectId("5af2c401a003533a8abf4e57"), "name" : "Dan Brown", "test_id" : 12345 } </code></pre> <p>So far i have to search on the collections independently . But not together </p> <p>For <code>author</code> search </p> <pre><code> ([{ "$match": { "name":"Dan Brown" } }, { "$lookup": { "from": "product", "localField": "test_id", "foreignField": "detail.test_id", "as": "users" } } ] ).pretty(); </code></pre> <p> And <code>title</code> has been accessed using the normal <code>find()</code> method EDIT 1:</p> <p>So this is what i have tried so far. Is this the right approach . Btw it's still not working though</p> <p></p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false"> <div class="snippet-code"> <pre class="snippet-code-js lang-js prettyprint-override"><code> db.product.aggregate ( [ { "$match": { detail.title : 'The random title' } }, { "$lookup": { "from": "author", "localField": "test_id", "foreignField": "detail.test_id", "as": "tb2" } }, { "$unwind": "$tb2" }, { "$match": { "": "agent" } } ] );</code></pre> </div> </div> </div>


<div class="post-text" itemprop="text"> <p>Below is my recordSigfox.php file. For now I am testing it from the addess bar: <a href="http://...server.../recordSigfox.php?data=e049d3c02b7f5542" rel="nofollow noreferrer">http://...server.../recordSigfox.php?data=e049d3c02b7f5542</a></p> <p>Tested separately and working: -The first part connects to mongoDB and creates a testData collection. -The second part decodes the hex message into its original components, a latitude and a longitude. I WANT TO RECORD THESE in testData. -The third part just lists the contents of testData.</p> <p>Apparent issue code:</p> <pre><code> $document = array( "Latitude" =&gt; $lt, "Longitude" =&gt; $lg, ); $manager-&gt;$collection-&gt;insert($document); </code></pre> <p>Full code:</p> <pre><code>&lt;html&gt; &lt;head&gt; &lt;title&gt;Unpack&lt;/title&gt; &lt;/head&gt; &lt;body&gt; &lt;?php //connect to DB $user = "muntean"; require '/var/composer/vendor/autoload.php'; $manager = new MongoDB\Driver\Manager("mongodb://localhost:27017"); echo "Connection to database successfully"; $collection = new MongoDB\Collection($manager, $user, 'testData'); //get data from the address bar: e049d3c02b7f5542 $_data = $_GET["data"]; $coord = unpack('flat/flon', pack('H*', $_data)); $lt = $coord['lat']; $lg = $coord['lon']; //echo lt shows: -6.6027679443359 //echo lg shows: 53.374187469482 $document = array( "Latitude" =&gt; $lt, "Longitude" =&gt; $lg, ); $manager-&gt;$collection-&gt;insert($document); //shows contect of testData when not empty $filter = []; $options = []; $query = new MongoDB\Driver\Query($filter, $options); $cursor = $manager-&gt;executeQuery("$user.testData", $query); print("The contents of the collection $user.testData are:"); print_r($cursor-&gt;toArray()); ?&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> </div>


现在最新的MongoDB版本为3.6,根据官网上的描述![图片说明]( 前三个貌似支持吃2d索引,现在官网建议是使用2dsphere,解决具体的业务,比如我们有一个区域查物的功能,这个区域可能是多边形,矩形或者圆形,那么如果我们的数据库表建立的是2dsphere 虽然也能查,但是其实是不走索引的,必须建立2d索引才行,有没有什么办法是我建立的是2dshpere索引,有相关的办法可以替代。


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