Linux, DevOps, Middleware and Cloud

In Last Post  "Overview on MongoDB"  we have discussed about the MongoDB. Now in this post we will discuss about the features and Use cases in Real World. Main features The following is a brief summary of some of the main features: Ad hoc queries MongoDB supports search by field, range queries, regular expression searches. Queries can return specific fields of documents and also include user-defined  JavaScript  functions. Indexing Any field in a MongoDB document can be  indexed  (indices in MongoDB are conceptually similar to those in RDBMSes). Secondary indices are also available. Replication MongoDB supports  master-slave replication . A master can perform reads and writes. A slave copies data from the master and can only be used for reads or backup (not writes). The slaves have the ability to select a new master if the current one goes down. Load balancing MongoDB scales horizontally using  sharding  The ...

MongoDB Overview MongoDB is the leading NoSQL database. Designed for how we build and run applications today, MongoDB (named from "huMONGOus," meaning "extremely large") empowers organizations to be more agile and scalable. It enables new types of applications, better customer experience, faster time to market and lower costs for organizations of all sizes. MongoDB is a general purpose, open-source database. It features: Document data model with dynamic schemas Full, flexible index support and rich queries Auto-Sharding for horizontal scalability Built-in replication for high availability Text search Advanced security Aggregation Framework and MapReduce Large media storage with GridFS Instead of storing data in rows and columns as one would with a relational database, MongoDB stores a binary form of JSON documents (BSON). Relational databases impose flat, rigid schemas across many tables. By contrast, MongoDB is an agile NoSQL...

Hi Friends, Sometimes when you want to remove any packages installed on Server using RPM, you will get errors as " error: "" specifies multiple packages ". To get ride of this error, you have to use "--allmatches" option available with RPM command. Below is example where I have tried to remove "cups-libs-1.3.7-30.el5" from server. Actually here we have "cups-libs-1.3.7-30.el5" installed for i386(32 bit) as well as x86_64(64 bit). So there are two copies of a single package available. Example : ~$ sudo rpm -qa | grep cups cups-libs-1.3.7-30.el5 cups-libs-1.3.7-30.el5 ~$ sudo rpm -e cups-libs-1.3.7-30.el5 error: "cups-libs-1.3.7-30.el5" specifies multiple packages ~$ sudo rpm -e  --allmatches cups-libs-1.3.7-30.el5 error: Failed dependencies:         libcups.so.2()(64bit) is needed by (installed) gtk2-2.10.4-21.el5_7.7.x86_64         libcups.so.2()(64bit) is needed by (installed) paps-0.6.6-20.el5.x86_6...