Cassandra and MongoDB are both âNoSQLâ databases, but the reality is that they are very different . They have very different strengths and value propositions â so any comparison has to be a nuanced one. Letâs start with initial requirementsâ¦ Neither of these databases replace RDBMS, nor are they âACIDâ databases.
If your laptop is running on no more than 512MB of RAM with Windows XP or no more than 1GB of RAM with Windows Vista or Windows 7, you should upgrade. You'll notice a significant difference in system performance after upgrading to 2GB with XP or Vista, or to 4GB with Windows 7.
So you've upgraded your PC with 8GB of system RAM, only to find out that Windows doesn't see all of it. The reason is simple: 32-bit versions of Windows XP, 7, or Vista cannot use more than 4GB of system RAM âat least not without an ugly and unsupported hack.