PL/SQL Collection Data Types

A collection is an ordered group of elements, all of the same type. Each element is identified by a unique subscript that represents its position in the collection PL/SQL provides three collection types − Index-by tables or Associative array Nested table Variable-size array or Varray VARRAY Varrays is hold a fixed-sized sequential collection of elements .. All varrays… Read More »

Yogesh Upreti

What is PL/SQL Records Data Types

A PL/SQL record is a composite data structure that is a group of related data stored in fields.  Records are composed of a group of fields, similar to the columns in a row . The %ROWTYPE attribute lets you declare a PL/SQL recordthat represents a row in a database table, without listing all the columns. PLSQL handle three type of Records 1)User- Define… Read More »

Yogesh Upreti

Bulk Collect and Bulk Bind

Retrieve many row in single fetch and improve the speed of data retrieval by less context switch. Oracle server used two engine to run PL/SQL block and subprogram. 1) The PL/SQL   runtime engine , which  run  all procedural line of code but passes the SQL statement to the SQL engine. 2)The SQL engine parse and executes the SQL… Read More »

Yogesh Upreti

How to Install MongoDB 3.2 on CentOS/RHEL

This article will help you to install MongoDB 3.2.X on CentOS, and RHEL . MongoDB is a free, cross-platform, open source, NoSQL document-oriented database. MongoDB is available as two editions, Community and Enterprise edition. MongoDB community edition is free for personal usage, whereas enterprise edition is paid version that have more features and support than the community edition. In this article, we will… Read More »

Bharat Negi

HIVE USES

Uses of HIVE 1. The Apache Hive distributed storage. 2. Hive provides tools to enable easy data extract/transform/load (ETL) 3. It provides the structure on a variety of data formats. 4. By using Hive, we can access files stored in Hadoop Distributed File System (HDFS is used to querying and managing large datasets residing in) or in other… Read More »

Abhishek Sharma

What is Hive in Hadoop?

Apache Hive is a data warehouse system for Hadoop, which enables data summarization, querying, and analysis of data by using HiveQL (a query language similar to SQL). Hive can be used to interactively explore your data or to create reusable batch processing jobs. After you define the structure, you can use Hive to query that data without knowledge… Read More »

Abhishek Sharma

Cap Theorem

The BASE acronym was defined by Eric Brewer, who is also known for formulating the CAP theorem. The CAP theorem states that a distributed computer system cannot guarantee all of the following three properties at the same time: Consistency:  every read would get you the most recent write,  all executions of reads and writes seen by all nodes… Read More »

Bharat Negi

SQL vs. NoSQL; An Overview

In this article, we’ll outline the differences between SQL and NoSQL, the vast array of differences within NoSQL technologies themselves, and discuss if  RDBMS  really are a thing of the past. NoSQL is a category of databases distinctly different from SQL databases. NoSQL is often used to refer to data management systems that are “Not SQL” or an… Read More »

Bharat Negi

Mysql useful production query script

How to start MySQL # service mysqld start # /etc/init.d/mysqld start How to set root password in MySQL # mysqladmin password “redhat” How to Login in Mysql # mysql -u root -predhat mysql> How to change root and Users password mysql> UPDATE mysql.user SET Password=PASSWORD(‘redhat123′) WHERE User=’root’; How to Create database mysql> create database DB-NAME; How to Check… Read More »

Bharat Negi

What is and why Nosql and What is big data?

NoSQL, or “not only SQL,” offers a new approach to managing large volumes of structured, semi-structured and unstructured data. NoSQL distributes workloads across commodity hardware which enables cost effective storage, processing and analysis of disparate data sets quickly. As an open source platform, NoSQL encompasses a wide variety of different database technologies that were developed in response to… Read More »

Bharat Negi