What is Massively Parallel Processing (MPP)

With the advent of Big Data sets mainstream technologies like Massively Parallel Processing (MPP) systems is experiencing vital growth. Let’s discuss about what is MPP or Massively Parallel Processing (MPP)

Update and Delete in Correlated Sub query

Correlated sub queries as you all know are used for row-by-row processing. Here each sub query is executed once for every row of the outer query. The oracle server performs a correlated subquery when the subquery references a column from a table referred to in the parent statement. 

The general for of a correlated subquery is:

select column1, column2, . . . . . . .

from table1 outer

where [column1] operator (select column1, column2,

from table2 where expr1= outer.expr2);

To read more about Sub queries please refer our previous post

http://dwhlaureate.blogspot.in/2012/08/sub-queries-in-oracle.html

Now will see how to use correlated update and delete statements 

“ VoltDB ” - NewSQL DBMS For High Velocity Applications

VoltDB is a high performance scalable RDBMS and NewSQL Database primarily for Big Data, high velocity OLTP and Real-time analytics designed by Michael Stonebraker, Sam Madden, and Daniel Abadi.

It was one of the NewSQL databases first introduced as open source product in 2010.Demand for high scale and in memory databases(which means it depends mainly on main memory for storage) in the market has shaped great aperture for VoltDB.

Introduction To NewSQL

NewSQL is a new class of Databases products that offers high performance and scalability like NoSQL for online transaction processing and also incorporates the relational database properties like SQL and ACID (atomicity, consistency, isolation and durability) transactions.

The NewSQL architecture (distributed systems architecture) significantly reduces overhead and is proficient of running on a large number of nodes without suffering bottlenecks. Also they conserve the high-level language query potential of SQL. NewSQL is now considered as an alternative to NoSQL.