NoSQL Databases

137

Solutions

267

Contributors

A NoSQL database provides a mechanism for storage and retrieval of data which is modeled in means other than the tabular relations used in relational databases. Motivations for this approach include: simplicity of design, simpler "horizontal" scaling to clusters of machines and finer control over availability. The data structures used by NoSQL databases (e.g. key-value, wide column, graph, or document) are specified from those used by default in relational databases, making some operations faster in NoSQL. Sometimes the data structures used by NoSQL databases are also viewed as "more flexible" than relational database tables.

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I am about to begin a large research project using natural language processing and web crawling. So, I am wondering about what AWS can offer for a scalable platform to undertake what may be a large amount of processing. I can see the advantages of having them handle everything for me. But I can also see that hardware costs can be super cheap.

I have no real experience setting up my own network or building my own desktop machines, so, I would certainly lose time on configurations.
 
What are the pros and cons of either plan?


Thanks.
0
Hi we have a client running 2 somewhat large databases on the Firebird platform.

My understanding is its an open source variant of SQL.

The database files are basically like this:
 
DATABASE1.FDB    = 2Gig
DATABASE1STORAGE.FBD   = 65Gig

I have been trying to find a nice utility to create daily BAK files of both of these databases.

DATABASE1.BAK
DATABASE1STORAGE.BAK

We then want to back these up offsite daily,  rather than try to Shadow copy the FDBS etc

Anyone have experience here?
Thanks
0
I am moving into Big Data Industry with new jobs. Just wanted to know if there are any links for me to get some real time scripting examples.
0
Hello , if someone can comment and explain for me this technically what is code is doing what behind logic and more importantly the once i did comment on top in this code below and about mongo db how can be treated, thanks

<?php

error_reporting(1);

ini_set("log_errors", 1);
ini_set("error_log", "/tmp/php-error.log");
$date = date("Y-m-d H:i:s");
error_log("$date: Hello! Running script /roadyo_base.php" . PHP_EOL);

require('../Models/config.php');
require('../Models/Pubnub.php');

$pubnub = new Pubnub(PUBNUB_PUBLISH_KEY, PUBNUB_SUBSCRIBE_KEY);
//can anyone explain for me technically what is going on with MONGO DB
$con = new MongoClient("mongodb://" . MONGODB_HOST . ":" . MONGODB_PORT . "");
$db = $con->selectDB(MONGODB_DB);
if (MONGODB_USER != '' && MONGODB_PASS != '')
    $db->authenticate(MONGODB_USER, MONGODB_PASS);

$favourite = $db->selectCollection('favourite');
$booking_route = $db->selectCollection('booking_route');

$location = $db->selectCollection('location');

$location->ensureIndex(array("location" => "2d"));

$use = array('pubnub' => $pubnub, 'location' => $location, 'favourite' => $favourite, 'booking_route' => $booking_route, 'db' => $db);

$pubnub->subscribe(array(
    "channel" => APP_PUBNUB_CHANNEL,
    "callback" => function($message) use($use) {
        //what (int) means
        $a = (int) $message['message']['a'];

        $args = $message['message'];

        if ($a == 4) { //update driver location
            if ($args['devId'] == '')
     

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0
A newbie question: it seems that mongo does not by default describe a hierarchical structure. So if i were using something like xpath in xml, i could find the parents of a giving node. Am i correct in thinking that you need to 'build-in' tree-like relationships (with say 'parent') to be able to do that?
0
I have mongoDB collection and for the documents added to the collection I used timestamp field to capture the current time stamp with this format:
2016-03-19T15:49:46-05:00

I am looking for a find query to return all documents added to data base in past 24 hours.

I would appreciate your help.
0
Hi Experts,

Is there anything other than sqlite that could be used to store records really easily for a webapp?  Something entity-driven would be great - or anything super simple?

Thanks!
Mike
0
I've managed to install MongoDB, and have it running successfully on my Windows 10 system. The one thing I found surprising, was that I could not run mongod.exe nor mongo.exe from GitBash, so I am wondering why that might be the case?

Note: I can run mongod.exe and mongo.exe via the Windows Command Prompt. The reason I prefer GitBash is because it allows me to zoom in, thus making the text more viewable.
0
I usually use sql server and sql server management studio.

I'm new to MongoDB.

I installed MongoDB. Then with windows command prompt I verified that I installed it correctly.
I walked through the tutorial of installation on the MongoDB website.

Does MongoDB have a graphical user interface tool like sql server does in Sql Server Management Studio that I can use on a Windows pc?
0
What are some of the technologies that facebook / twitter use to store and search their massive data graphs?
I'm looking for something that will have capabilities to search massive amounts of data that will be growing constantly.
0
MongoDB collection insert document fails

I'm not sure why its failing.

db.post3.insert([
{
      title: 'MongoDB Overview', 
      description: 'MongoDB is no sql database',
      by: 'tutorials point',
      url: 'http://www.tutorialspoint.com',
      tags: ['mongodb', 'database','NoSQL'],
      likes: 100
},
{
      title: 'NoSQL Database', 
      description: 'NoSQL database doesn't have tables',
      by: 'tutorials point',
      url: 'http://www.tutorialspoint.com',
      tags: ['mongodb', 'database','NoSQL'],
      likes: 20, 
      comments: [  
      {
            user:'user1',
            message: 'My first comment',
            dateCreated: new Date(2013,11,10,2,35),
            like: 0 
     }
   ]
}
])

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fail.jpg
0
Hi Experts,

I am using Redis Cache
First time only my method will hit DB and get the values
Next time if i want same values i am going to get it from redis cache manager.

problem is
some time redis server going down.
that time my code breaking down.

i want to do check like

if the server is down skip getting the values from the cache manager,need to get it from DB.
even when i moved to other environment like dev environment to production
if the redis server not installed that time also my code should not break.

can some one suggest me how to do?

 @Autowired
    private CacheManager<UserGroupToGroupType> cacheManager;
    
    @Override
    public List<UserGroupToGroupTypeDTO> getGroupForCustomerIdAndGroupType(String customerId, Integer groupTypeId) {
        UserGroupToGroupType groupToGroupType=cacheManager.findById(customerId);
        if(groupToGroupType!=null){
            return groupToGroupType.getUserGroupToGroupTypeDTOs();
        }
        List<Object[]> namedFiltersList = userGrpToGrpDao.getGroupForCustomerIdAndGroupType(customerId, groupTypeId,
                UserGroupToGroupTypeDAOImpl.Readset.ID_GID_GNAME.getName());
        return UserGroupToGroupTypeServiceHelper.convertDotoDTOforID_GID_GNAME(namedFiltersList,cacheManager,customerId);
    }
}

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0
hi how do i add column in mongo db where do i run this
db.your_collection.update({},{$set : {"new_field":1}},false,true)
0
I've read about caching the asp.net viewstate using "NCache".  Can this also be done with a Redis cache such as from Azure?

0
hi i have gui which get value from mongo db how can i populate value this is my gui
Capturetab12.PNGsomething like this
hi how can I search value from database using combobox for example I enter username and return the detail of that username something like this
import javax.swing.*;
import org.jdesktop.swingx.autocomplete.AutoCompleteDecorator;//where do I get this am getting error is not recognise
import java.awt.*;

public class Demo {

    JFrame frame = new JFrame("");
    AutoCompleteDecorator decorator;
    JComboBox combobox;

    public Demo() {
        combobox = new JComboBox(new Object[]{"","Ester", "Jordi",
            "Jordina", "Jorge", "Sergi"});//I what to searc from database
        AutoCompleteDecorator.decorate(combobox);
        frame.setSize(400,400);
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLayout(new FlowLayout());

        frame.add(combobox);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        Demo d = new Demo();
    }
}

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0
hi how can I search value from database using combobox for example I enter username and return the detail of that username

this is my code
      
public CreateUserGUI()
	{
		
	//	backPanel = new JPanel(new GridBagLayout());
	//	topPanel = new JPanel(new GridBagLayout());
		JTabbedPane jtp = new JTabbedPane();
		 getContentPane().add(jtp);
		
		
		
    	JPanel jp1 = new JPanel();
        JPanel jp2 = new JPanel();
        JPanel jp3 = new JPanel();
        JPanel jp4 = new JPanel();
		
		nameLabel = new JLabel("Name : ");
	    txtName = new JTextField(15);
		txtName.setMinimumSize(txtName.getPreferredSize());
		
		
		 JLabel label1 = new JLabel();
        label1.setText("You are in area of creating new User");
        JLabel label2 = new JLabel();
        label2.setText("You are in area of Updating user Information");
        JLabel label3 = new JLabel();
        label3.setText("You are in area of seting  user Inactive");
        JLabel label4 = new JLabel();
        label4.setText("You are in area to Search user Information");
        
        
        
         
			
	    	surnameLabel = new JLabel("Surname : ");
	    	txtSurname = new JTextField(15);
	    	txtSurname.setMinimumSize(	txtSurname.getPreferredSize());
	    	
	    	
	    	usernameLabel = new JLabel("Username : ");
	    	txtUsername = new JTextField(15);
	    	txtUsername.setMinimumSize(	txtUsername.getPreferredSize());
	    	
	    	passwordLabel = new JLabel("Password : ");
	    	passwordField = new  

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0
I have a JDBC ResultSet that has data in a row fashion, e.g. name | value, I want to transpose that data into columns and put it into a csv file.  Can someone help me with the algorithm?  Thanks.
0
I have a production mongo 2.6 DB running across 9 Linux instances in AWS. It is replicated and sharded across 2 regions, and all disks are in RAID10. I'm working to restore the prod DB into a staging environment that has replication turned on but sharding not configured yet. The dump is 103GB. 91GB of which resides in a single collection.

Attempting to restore the entire DB in stage fails reliably when the restore reaches the creation of indexes on the large collection. The error is not very informative, and unfortunately this is all I get even with log verbosity turned up:

Socket recv() conn closed? 10.0.0.1:27017 
SocketException: remote: 10.0.0.1:27017 error: 9001 socket exception [CLOSED] server [10.0.0.1:27017] 
DBClientCursor::init call() failed 
User Assertion: 10276:DBClientBase::findN: transport error: 10.0.0.1:27017 ns: c_knowledgebase.$cmd query: { getlasterror: 1 } assertion: 10276 DBClientBase::findN: transport error: 10.0.0.1:27017 ns: c_knowledgebase.$cmd query: { getlasterror: 1 }

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The nature of the error made me suspect the restore exhausted a resource. Therefore in order to work around the issue I tried various permutations of the following:


1. using beefy EC2 instances on SSDs
2. review common mongo Linux tuning suggestions (overcommit, and ulimit settings)
3. restoring the DB in a phased approach (restoring the large collection as a separate step and making the indexes manually one at a time)

If I do #1 and #2 together I'm able to get the entire DB to restore. This doesn't solve my problem, however, as I need to understand what the root problem is, and more importantly I need to have a consistent DB restore procedure that is running on 1:1 hardware that prod is on. I'm hoping someone can offer some insight into why a restore fails under these conditions.
0
Hi,
I'm new to mongodb. How would I fix a typo in an object? I tried this query but it resulted in an error of "Unexpected token ILLEGAL"

db.mer22.update({_id:12345},{$set{"yDescription":"Candy"}})

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1
Hi,

I want to learn about the Mongo DB and Im looking for good book as a start point.

Any suggestion on books or texts for beginners that has exp. with Oracle already (not sure if its relevant).

Tks,
Joao
0
Currently I am looking how the backup/restore be done in Cassandra. We've setup a three node cluster in AWS. I understand that using nodetool snapshot tool we can take a snapshot but it's bit cumbersome process.

My idea is : Make use of EBS snapshot because they're more durable and easy to setup but one problem which I see with EBS is inconsistency backup. Hence, my plan is run a script prior to taking EBS snapshot which would just run flush command to flush out all the memtable data and copies it on to the disk(SSTable) and then prepares the hard link with flushed SSTable. Once that's done, initiate the EBS snapshot, this was we can address the inconsistency issue which we might face if we only use EBS snapshost.

Please let me know if you see any issue with this approach or share your suggestions.
0
In this code fragment:, when I invoke the Python interpreter, I get the following error:

M:\MongoDB University\Lecture 1\bottle_framework_url_hand
  File "hello_world.py", line 15
    elif (restaurant == "abcde"):
       ^
SyntaxError: invalid syntax


   
if (restaurant == None or restaurant == ""):
        restaurant="***No restaurant selected***"
    elif (restaurant not in myrestaurants): # trying something extra...
	restaurant = "**Invalid restaurant selected**"

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As far as I can tell, my syntax is OK. (e.g. a colon after the elif line and proper indentation. What am I missing?
Thanks,
Steve
0
Hi,

I am taking a course through MongoDB University --- online. They provided me with same sample Python (.PY) files. I tried viewing one in NOTEPAD, but the line breaks are missing, so everything is run together. I know the breaks are there, b/c when I display the file via the TYPE command, it shows properly.

How do I work around this issue? Is there a Python editor on my system?

Thanks,
Steve
0
I am new to the Node.js,MongoDB and Angular JS framework.. Where can I find some good material to do a quick start?

I also would like to know the advantages of the above technologies.
0
Dear
        our system use activemq + redis + mysql, now i would like to setup activemq cluster, how many server i needed at least ? is there any user guide for build up activemq cluster?
0

NoSQL Databases

137

Solutions

267

Contributors

A NoSQL database provides a mechanism for storage and retrieval of data which is modeled in means other than the tabular relations used in relational databases. Motivations for this approach include: simplicity of design, simpler "horizontal" scaling to clusters of machines and finer control over availability. The data structures used by NoSQL databases (e.g. key-value, wide column, graph, or document) are specified from those used by default in relational databases, making some operations faster in NoSQL. Sometimes the data structures used by NoSQL databases are also viewed as "more flexible" than relational database tables.

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NoSQL Databases
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