About Database Systems

Relational Database Systems are important part of information technologies. We are using databases a lot of applications and programs. The most important element is performance.

Relational Database Management Systems(RDBMS) basically contain tables, relations between tables, columns and rows. This kind of structures provides availability and durability for systems but causing a little latency. Because when you run a query on db systems, you need a little bit time, there is an execution time. We are using SQL(Structured Querying Language) codes for querying databases. RDBMS queries  run on execution plan. It does not matter even if the DB data is on memory, your response will be delayed for some time.

Several techniques have been developed to prevent this situation. For example: views, indexes, stored procedures etc. They do not work while your data size keeps growing. In this situation, databases should be used more for data storage purposes. You can export your data to a NoSQL database and then query If you want to get any data from database. Because NoSQL databases provide better performance than relational databases.

 

Why are NoSQL databases faster than SQL databases?

There are not any relations and multiple tables on nosql databases. Therefore nosql databases execute queries quickly according to sql databases. This is the main reason.

There is another reason: Data size is less than according to sql databases.

What are the risks?

SQL databases have more strong management and redundancy. You may be  struggling with replication and backup/restore etc. activities.

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About Anycast

Anycast is a network addressing and routing methodology in which datagrams from a single sender are routed to the topologically nearest node in a group of potential receivers, though it may be sent to several nodes, all identified by the same destination address.

Anycast addressing routes datagrams to a single member of a group of potential receivers that are all identified by the same destination address. This is a one-to-nearest association.

anycast

For example: DNS service is a distributed service over multiple geographically dispersed servers.

Google Cloud DNS service using anycast methodology.

 

 

Disk Usage on Linux

If you learn disk usage on your linux machine, you can use “df” command. This command gives you used space, available space, used percent for partitions and folders.

df

df1

Also, “df -h” command more understandable for you,

df2

 

 

Task Manager for Linux – htop

You can get a usefull task manager for your linux machines, htop

I installed htop on my ubuntu and debian machines.

The first thing to do, is to verify if your repositories are up-to-date

  • apt-get update

The next step is to install “htop”:

  • apt-get install -y htop

The “-y” argument above, automatically accepts the package installation!

and than you can monitoring your tasks;

htop