In the previous post i.e Document
Replacement in MongoDB we have
seen how we were updating the
document – first by getting the
document using findOne() , then
updating its values and finally
putting it back in the collection.
We can also achieve the same task
in a single step i.e skipping findOne() invocation and by using atomic update modifiers provided by mongodb. This post will focus on update mongodb java example. Continue reading Atomic Update MongoDB Java Example→
In the previous posts we have seen examples
on how we can query a MongoDB using Java. We have seen different ways in which we can invoke find() method and how to do comparison querying and logical querying. This post will focus
on updating of our existing documents present in our mongo database using Java.
I am sure that by this time all of us have already heard about the Heartbleed ,that made almost every encrypted sensitive data i.e passwords,credit card details etc vulnerable to external attacks.
These days almost each and every website asks user for registration and provides them with an username and password for there future interaction with the website.Today HTTPS protocol is the defacto standard for sending the sensitive data to the server and behind the scenes Secure Sockets Layer (SSL) and Transport Layer Security(TLS) protocols which make sure that every transaction between the client and server is secure. Continue reading Heartbleed – What went wrong ?→
This post will focus on the logical
operators that are available in
momgodb.I will use Java for the
illustration purpose of these
operators. You can use any of
the language for which mongo
driver is available. For the comparison operators you can refer the previous post here.
There are 4 logical operators that have been documented in mongodb specs.
We will continue with the same example that we have seen in the previous post. Continue reading Logical Querying MongoDB Java Example→
In the previous post we have seen
different variations of find() method ,
but in real life we need much more than the exact matching e.g we want to query in ranges (using in ) , combine multiple conditions together (using OR , AND) , using negation etc. In this post we will cover the comparison query operators that comes under the conditional querying in MongoDB :
One of the new features that we will see in Java8 is the introduction of Metaspace. Metaspace is nothing but a replacement of our old friend PermGen (Permanent Generation) space.
What is PermGen?
The permanent Generation is part of your heap space that is actually used to store meta-data information for the classes created by users and prior to Java 7, it is also used to store interned Strings (interned strings – used to remove String duplicates by internalizing them to reduce memory consumption). As of Java 7, intern strings also moved as a part of heap space to make the more space available in Continue reading Metaspace in Java8→
In the earlier post Mongodb java Hello World Example we have seen some basic operations on the MongoDB and searching the document was one of them there we had used find().In this post we will more focus on querying mongdb with java using find() method that is basically used for querying documents in mongodb collections. We will see that how we can use find() in different ways to meet our query needs.Below are the 4 basic scenarios that we are going to cover under querying mongodb java example.
Fetching all the documents from a collection.
Fetching a subset of documents from a collection.
Fetching only selected keys of a document from a collection.
Exclude some keys of a document from a collection.
While searching something on the MongoDB over the internet somehow (yes you heard it right , a google fan) i selected Bing search engine in the mozilla search tool bar and next thing that i saw on my search results page is the message from the Microsoft that you have earned 1 credit. Initially I ignored it and i changed my search criteria because earlier one was not giving me the result i was looking for , this time i observed that those credit becomes 2.
Now it increased my curiosity and i thought it might be the same thing like what stackoverflow offers but there they call it reputation (and it matters). So, i thought microsoft also started Continue reading Microsoft Bing Search and Earn Program→
In the previous post we have seen some of the basics on the primary keys and ObjectId in MongoDB.Now its time to get our hands dirty with some code , here I am using Java to interact with our mongo database. In this MongoDB Java Hello World example we will cover the following points : –