mongo express

We are always in contrast to see their strengths and weaknesses, for MongoDB is also the same, comparative learning let us as soon as possible to grasp the basic knowledge about MongoDB. MongoDB vs. mysql command A relational database is generally composed of three levels of databases (database), tables (table), records (record). Non-relational database MongoDB are composed of three levels of databases (database), Collections (collection), document objects (documents). MongoDB for tables in re

) {mongoclient client=null; try {mongoclientoptions.builder build = new Mongoclientoptions.builder (); With data maximum connection number build.connectionsperhost (50); If all of the current connection are in use, then each CONNECtion can have 50 threads queued for Build.threadsallowedtoblockforconnectionmultiplier (50); Build.connecttimeout (1 * 60 * 1000); Build.maxwaittime (2 * 60 * 1000); Mongoclientoptions options = Build.build (); InetAddress inetaddress; inetaddress =

Turn from: http://hi.baidu.com/zwfec/item/3cfecfabafda3a258819d38b Today, look at the server, found that Mongod start not up, prompted Sun June 2 12:27:02 error:couldn ' t connect to server 127.0.0.1:27017 src/mongo/shell/mongo.js:91 Error Look up the solution on the Internet, most people say set up dbpath, this is to solve the problem, but not to find the root cause of the problem, The root of the problem is that the machine illegal shutdown caus

--maxconns--fork--logappend Start a third node:/usr/local/mongodb/bin/mongod--port 28011--oplogsize--dbpath=/sdb1/liujijun/data/data/r1/--logpath=/ Sdb1/liujijun/data/log/r1.log--replset rs1/127.0.0.1:28010,127.0.0.1:28012--maxconns--fork--logappend 3: Chain succession to select a node #/usr/local/mongodb/bin/mongo--port 28010 > config={_id: ' rs1 ', Members: [{_id:0, Host: ' localhost:28010 '},{_id:1, Host: ' localhost:28011 '},{_id:2, host : ' local

Use userDbShow DBSDb.dropdatabase ()Db. Collection_name.insert (document)Exp:Db.user.insert ({name: "user1", Password: "123456"})Hint: Writeresult ({"ninserted": 1}) indicates successful insertionDb.user.find ()Hint {"_id": ObjectId ("56946FBA3A18F4867AECBCD1"), "name": "user1", "Password": "123456 "}> test={name: "user2", Passsword: "123456"}{"Name": "User2", "Passsword": "123456"}> Db.user.insert (Test)Writeresult ({"ninserted": 1})> Db.user.find (){"_id": ObjectId ("56946FBA3A18F4867AECBCD1")

Tags: log logs database operation record Ffline false data new Db.getcollection ('Product').Update({Status: "Offline"},{$Set: {status: "Online"}},false,true) update, change all status offline to online, note quotes db.collection.Update(criteria, objnew, Upsert, Multi) The description of the four parameters is as follows: The criteria:update query condition, similar to the Objnew:update object within the where in the SQL update query and some updated Operator (such as $, $inc ... ), and so on, c

Tags: test jsb default TAC cannot fonts size art throughThrough the Rs.status () command we can query to each node to run normally.First, the data synchronization testInsert on port 28011, 28012:Because secondary is not allowed to read and write, in the application of more than read, the use of replica sets to achieve read and write separation. By specifying Slaveok at the time of connection, or by specifying the secondary in the main library, the pressure of reading is shared by the primary and

watermark/2/text/ahr0cdovl2jsb2cuy3nkbi5uzxqvdgfuz2xpdxfpbmc=/font/5a6l5l2t/fontsize/400/fill/i0jbqkfcma==/ Dissolve/70/gravity/center ">watermark/2/text/ahr0cdovl2jsb2cuy3nkbi5uzxqvdgfuz2xpdxfpbmc=/font/5a6l5l2t/fontsize/400/fill/i0jbqkfcma==/ Dissolve/70/gravity/center ">watermark/2/text/ahr0cdovl2jsb2cuy3nkbi5uzxqvdgfuz2xpdxfpbmc=/font/5a6l5l2t/fontsize/400/fill/i0jbqkfcma==/ Dissolve/70/gravity/center ">MONGO database--Non-relational database

Plan to make a back word Web application, very not successfully found the resources, to get a. bak file, import to SQL Server is simple, now I want to take the data to Mongolab, encountered some pits, specially recorded (old, can't remember AH)Mongolab Support Binary,json,csvSo I'm exporting the data as a. csv1. Database-task-export data2. Select SQL Server Native Client3. Next select a flat file destination4 Next Preview5. Implementation results6. If you directly execute the pour commandReturnM

In our previous blog, we focused on how to build a MongoDB replica set under the Windows platform. Detailed Blog Address:As space is limited in the previous article did not verify the results, in this blog we mainly test:Through the Rs.status () command we can query to each node to run normally.First, the data synchronization testInsert on port 28011, 28012:View reason: Find the answer onlineFirst of all this is normal, because secondary is not allowed to read and write, in the application of wr

Federated query with and, or multiple conditionsAge condition (and condition)Basicdblist condlist = new Basicdblist ();Basicdbobject cond = new Basicdbobject ();Cond.put ("$gt", 0);Cond.put ("$lte", 40);Basicdbobject composecod = new Basicdbobject ();Composecod.put ("Age", cond);Condlist.add (COMPOSECOD);Name conditionBasicdbobject Namecond = new Basicdbobject ();Namecond.put ("name", "name");Condlist.add (Namecond);Query condition combination (or condition)Basicdbobject Searchcond = new Basicdb

composed of three layers: database, collection, and document. Mongodb does not have the concept of the relationship between rows and columns for tables in relational databases, which reflects the free features of the mode. The syntax commands are shown in the following table. MySQL MongoDB Description Mysqld Mongod Server daemon Mysql Mongo Client tools Mysqldump Mongodump Logical backup too

Source: http://www.educity.cn/wenda/361741.htmlPymongo Delete data according to ObjectId _idWant to delete data, according to _ID, is the most reliable, concrete methodBecause _id is a objectid () object, you first have to introduce a pair of images, where are the objects?Reading, found is a Bson fragment generated Objectid, then will not put this object in Bson,Try it.From Bson import ObjectIdCollgroup.remove ({"_id": ObjectId (' _id string ')})PerformIt's OK ..."

[Tom @ agilysys: Data] $ mongod -- replset MyApp -- dbpath ~ /Mongoreplicate/data/node1 -- port 4000[Tom @ agilysys: Data] $ mongod -- replset MyApp -- dbpath ~ /Mongoreplicate/data/node2 -- Port 4001[Tom @ agilysys: Data] $ mongod -- replset MyApp -- dbpath ~ /Mongoreplicate/data/Arbiter -- Port 4002 Thu Jun 20 18:48:30 [rsstart] replset can't get local. system. replset config from self or any seed (emptyconfig)Thu Jun 20 18:48:40 [rsstart] replset can't get local. system. replset config from s

Mongo java and/or multi-condition query, using java// And, or multi-condition joint Query// Age condition (and condition)BasicDBList condList = new BasicDBList ();BasicDBObject cond = new BasicDBObject ();Cond. put ("$ gt", 0 );Cond. put ("$ lte", 40 );BasicDBObject composeCod = new BasicDBObject ();ComposeCod. put ("age", cond );CondList. add (composeCod );// Name ConditionBasicDBObject nameCond = new BasicDBObject ();NameCond. put ("name", "name ");

Mongo db windows installation, mongodb1. Download the installation packageHttps://fastdl.mongodb.org/win32/mongodb-win32-x86_64-2008plus-ssl-3.0.0-signed.msi? _ Ga = 1.22066811.15995322.16.142368396After the download is complete, place the installation file under the directory you want to install.2. InstallOpen the run box with win + r and enter "cmd" to run. (Run as Administrator) switch the directory to the installed directory and execute the follow

1. Connect to the server:Mongo2. Connect to the databaseUse dbname3. Querying the names of all collectionsDb.getcollectionnames ()4. Querying data for a collectionDb.collection.find ()Db.collection.find ({columnname: "value"})//accept only one parameter5. Inserting data in a collectionInsert a single column of data: Db.collection.insert ({columnname: "value"})Insert a two-column data: Db.collection.insert ({columnname1: "value1", columnname2: "value2"})Insert multiple records: for (i=1;i6. Updat

= Query.and (Query.eq ("MenuId", PID)); var update = Update.set ("child", menu); DAL. Dalmenu.update (Queryid, Update);So here's the problem, Update.set () the second parameter of this function is bsonvalue type, I can't put a set as a parameter, the Update method must also specify a field to modify, and then I suddenly do not know how to modify.Then I started Baidu (since Google highlighted China after I started Baidu), the resul

First, the indexDb.person.remove ({})for (Var i=0;ivar rand = parseint (I*math.random ());Db.person.insert ({"Name": "XX" +i, "age": Rand})}Db.person.find ({"Name": "XX" +1000}). Explain ()Stage is Collscan description does not go index, walk index words will show IXSCANDb.person.ensureIndex ({"Name": 1})Here we use the Ensureindex to build an index on name. "1": Indicates ascending by name, "1": Indicates descending by name.Db.person.getIndexes ()Db.person.dropIndex ({"Name": 1})Db.person.ensur

Spring + Mongo + Morphia ConfigurationSpring Configuration Xmlns: xsi = "http://www.w3.org/2001/XMLSchema-instance" Xsi: schemaLocation = "http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> Java DAO @ Repository Public class UserEntityDAO extends BasicDAO @ Autowired Protected UserEntityDAO (Datastore dataStore ){ S