Posts

Showing posts with the label Cloud

Featured Post

SQL Interview Success: Unlocking the Top 5 Frequently Asked Queries

Image
 Here are the five top commonly asked SQL queries in the interviews. These you can expect in Data Analyst, or, Data Engineer interviews. Top SQL Queries for Interviews 01. Joins The commonly asked question pertains to providing two tables, determining the number of rows that will return on various join types, and the resultant. Table1 -------- id ---- 1 1 2 3 Table2 -------- id ---- 1 3 1 NULL Output ------- Inner join --------------- 5 rows will return The result will be: =============== 1  1 1   1 1   1 1    1 3    3 02. Substring and Concat Here, we need to write an SQL query to make the upper case of the first letter and the small case of the remaining letter. Table1 ------ ename ===== raJu venKat kRIshna Solution: ========== SELECT CONCAT(UPPER(SUBSTRING(name, 1, 1)), LOWER(SUBSTRING(name, 2))) AS capitalized_name FROM Table1; 03. Case statement SQL Query ========= SELECT Code1, Code2,      CASE         WHEN Code1 = 'A' AND Code2 = 'AA' THEN "A" | "A

Social Media and Mobile Technology for Health care

Image
(People also click these jobs to  know skill set  and to apply  even from your phone!!) The ubiquity of mobile phone accessibility around the world is increasing. Worldwide the number of mobile phones in use grew from fewer than 1 billion in 2000 to around 6 billion in 2012. Recent estimates conclude that over 75% of the world' s population have access to a mobile phone (World Bank, 2012). Globally, there has been a rapid rise in the use of smart phones by consumers with over 1 billion Smart Phones subscribers (Approximately 30% of smartphone users are likely to use wellness apps by 2015, (Bjornland, Goh, Haanæs, Kainu, & Kennedy, 2012) with more than 30 billion mobile applications being downloaded in 2011 (World Bank, 2012). Along with this increase in penetration, there has been a significant increase in the development and deployment of mobile software applications across multiple computing platforms (e.g. smart phones, tablets and laptops). The most pop

How to achieve Virtualization in cloud computing real ideas

In order to run applications on a Cloud, one needs a flexible middleware that eases the development and the deployment process. Middleware Approach to Deploy Application on Cloud GridGain provides a middleware that aims to develop and run applications on both public and private Clouds without any changes in the application code.  It is also possible to write dedicated applications based on the map/reduce programming model. Although GridGain provides a mechanism to seamlessly deploy applications on a grid or a Cloud, it does not support the deployment of the infrastructure itself. It does, however, provide protocols to discover running GridGain nodes and organize them into topologies (Local Grid, Global Grid, etc.) to run applications on only a subset of all nodes. Elastic Grid infrastructure provides dynamic allocation, deployment, and management of Java applications through the Cloud.  It also offers a Cloud virtualization layer that abstracts specific Cloud computing provide

Hadoop: How to find which file is healthy

Image
Hadoop provides file system health check utility which is called "fsck". Basically, it checks the health of all the files under a path It also checks the health of all the files under the '/'(root). BIN/HADOOP fsck / - It checks the health of all the files BIN/HADOOP fsck /test/ - It checks the health of files under the path By default fsck utility cannot do anything for under replicated blocks and over replicated blocks. Hadoop itself heal the blocks.   How to find which file is healthy It prints out dot for each healthy file It will print a message for each file, if it is not healthy, also for under replicated blocks, over replicated blocks, mis-replicated blocks, and corrupted blocks. By default fsck utility cannot do anything for under replicated blocks and over replicated blocks. Hadoop itself heal the blocks. How to delete corrupted blocks BIN/HADOOP fsck -delete block-names It will delete all corrupted blocks BIN/HADOOP fsck -m

Understand Data power why quality everyone wants

Information and data quality is new service work for data intense companies. I have seen not only in Analytics projects but in Mainframe projects, there is the Data Quality team. How incorrect data impact on us Information quality problems and their impact are all around us: A customer does not receive an order because of incorrect shipping information. Products are sold below cost because of wrong discount rates. A manufacturing line is stopped because parts were not ordered—the result of inaccurate inventory information. A well-known U.S. senator is stopped at an airport (twice) because his name is on a government "Do not fly" list. Many communities cannot run an election with results that people trust. Financial reform has created new legislation such as Sarbanes—Oxley.  Incorrect data leads to many problems. The role of Data Science is to use quality data for effective decisions. What is information Information is not simply data, strings of numbers, lis

Big Data: Top Hadoop Interview Questions (4 of 5)

Image
1) What is MAP Reduce program? - You need to give actual steps in this program - You have to write scripts and codes 2) What is MAPReduce? -Mapreduce is a data processing model -It is combination of 2 parts. One is Mappers and the other one is Reducers 3)What will happen in Mapping phase? It takes the input data, and feeds each data element into the mapper 4)What is the function of Reducer? The reducer process all outputs from mapper and arrives at a final result 5)What kind of input required for Mapreduce? It should be structured in the form of (Key,Value) pairs 6)What is HDFS? HDFS is a file system designed for large-scale data processing under frameworks such as MapReduce. 7) Is HDFS like UNIX? No, but commands in HDFS works similarly to UNIX 8) What is Simple file command? hadoop fs -ls 9) How to copy data into HDFS file system? Copy a file into HDFS from local system 10) What is default working directory in HDFS? /user/$USER $USER ==> Your log

Big Data: Top Cloud Computing Interview Questions (1 of 4)

Image
The below are frequently asked interview questions on Cloud computing: 1) What is the difference between Cloud and Grid? Grid: -Information service -Security Service -Data management -Execution Manageement Cloud: - Maintains up-to-date information of resources -Create VMs according to user requirement -Application deploment -User management 2) What are the different cloud standards? -Interoperability standards -Security standards -Portability Standards -Governance and Risk standards 3) What are the two different sub-systems in Cloud computing ? -Management sub system -Resource sub system 4)What is Cloud compouting? The promise of cloud computing is ubiquitous access to a broad set of applications and services, which are delivered over the network to multiple customer. 5) Why we need specialized network for Cloud services? The public Internet is the simplest choice for delivering cloud-based services. In this model, the cloud provider simply purchases Inter

Big Data: Top NoSQL Interview Questions (2 of 5)

Image
1) What is most important character of NoSQL? High Availability 2)Different types of NoSQL databases? Key-Value stores Column Stores Graph Stores Document Stores 3)What is oracle NoSQL database? Oracle NoSQL Database is a distributed key-value database designed to provide highly reliable, scalable, and available data storage across a configurable set of systems. 4)What is the DB engine being used in Oracle NoSQL database? Oracle NoSQL Database uses Oracle Berkeley DB Java Edition as the underlying data storage engine. 5)What is oracle NoSQL database? Oracle NoSQL Database is a shared-nothing system designed to run and scale on commodity hardware. Key-value pairs are hash partitioned across server groups known as shards. At any point in time, a single key-value pair is always associated with a unique shard in the system. 6) What are unique features of Oracle NoSQL? Oracle NoSQL Database leverages the high availability features in Berkeley DB in order to provide res

Cloud Storage as a Service Basics(1 of 3)

Image
Cloud storage is a model of networked enterprise storage where data is stored in virtualized pools of storage which are generally hosted by third parties. Hosting companies operate large data centers, and customers that require their data to be hosted buy or lease storage capacity from these hosting companies. The data center operators virtualize the resources according to customer requirements and expose them as storage pools, which the customers can use to store data. Physically, the resource may span multiple servers and multiple locations. The safety of the data depends upon the hosting companies and on the applications that leverage the cloud storage. Cloud storage is based on highly virtualized infrastructure and has the same characteristics as cloud computing in terms of agility, scalability, elasticity, and multi-tenancy. It is available both off-premises and on-premises.  While it is difficult to declare a canonical definition of cloud storage architecture, object sto

Cloud Storage the real Points You Need to Read Now

Image
There are hundreds of different cloud storage systems, and some are very specific in what they do. Some are niche-oriented and store just email or digital pictures, while others store any type of data. Some providers are small, while others are huge and fill an entire warehouse. In this post, you will know about: Storage in Cloud The inside details of Cloud New things in Cloud Storage Storage of CLOUD One of Google’s data centers in Oregon is the size of a football field and houses thousands of servers.  The inside details of  Cloud Storage At the most rudimentary level, a cloud storage system just needs one data server connected to the Internet.  A subscriber copies files to the server over the Internet, which then records the data.  When a client wants to retrieve the data, he or she accesses the data server with a web-based interface, and the server then either sends the files back to the client or allows the client to access and manipulate the data

Cloud in India Rural Education

Image
Many a times we do things beyond a formal classroom without realizing that we are learning in the process. For example, an individual surfs and accesses material on the Internet in the form of audio, video, wiki and then goes ahead to even create and store information. Understanding the immense power of peer-to-peer learning, Classle, a Chennai-based startup has developed a cloud based education system for rural India. Classle gets lakhs of people together and enables them to connect to each other in thousands of communities available on open social network of Classle. People can connect with these communities to collaborate and share exchange resources in their chosen areas of interest. There are many features to collaborate in addition to make learning fun oriented. The cloud-based system enables students to access learning material free of cost, through their basic, low-cost mobile devices. The impact - more than 55 academic institutions have partnered with Classle-- almost all o