NoSQL Tour--cassandra Installation Chapter (i)

A little confused, the mind only to think of a word, "then go to learn it."

I am responsible for a part of the project to use the Cassandra, at that time also looked at points, but not too deep understanding, since the "learning momentum" is sufficient, then study it well.

As for the merits and demerits of NoSQL and relational databases, let's go straight to the point and finish the installation of Cassandra.

Official website: http://cassandra.apache.org/Download the latest stable version of 2.1.7, unzip me here to D-disk.

To configure environment variables:

To Win8, for example, right-click the computer picture on the desktop, select Properties, and create the Cassandra environment variable configuration as shown:

Command line (or cmd) input echo%cassandra% can show whether the setting is successful, here stole a trick, sometimes this environment variable need to restart, you can enter set%cassandra%=xxx (any value), and then close the current command line (CMD) window, The environment variable is overloaded, eliminating the restart of the computer.

To this installation is done, into the Cassandra installation directory of the Bin folder, double-click Cassandra.bat, the service will be formally launched, you want to close the command line (CMD) window directly on the line. What, you said your window flashed off and turned off directly. It doesn't matter, open a cmd (not command line), drag the Cassandra.bat with the left mouse button, enter the execution to see what the error prompts. Here's the mistake:

Unsupported Major.minor version 51.0

It is common that the JDK version is incorrect and this 2.1.7 version requires jdk1.7 support . Update it, and then we re-execute, what you said again error. I'm here to report this mistake:

warning! Powershell script execution unavailable.   ' PowerShell set-executionpolicy Unrestricted '   this user-account to run Cassandra with fully Featured   Thisto object Heaperror:could not create the Java Virtual MACHINE.ERROR:A Fatal exception has occurred. Program would exit.

The space is not enough. Win8 System of 6g of memory is not really big, but this is to make a noise. Open the Cassandra.bat file with Notepad (text editor) and see it actually initializes 2g of memory ....

This is a bit harsh. The XMS and xmx are changed to 1G, run again, this time finally good ....

NoSQL Tour--cassandra Installation Chapter (i)