If you have been using a relational database all this while then you must be aware of the fact that data is typically stored in rows. However, what you may not know is that a column-oriented database can also be used for the purpose of storing data. Just so you know if you use this type of database then the tables which contain your data are likely to be stored as sections of columns of data. Of course, in this situation, there will be no involvement of rows of data as you will be taking advantage of the columnar approach. 

The good news is that using a column-oriented database has its own advantages. In fact, it is believed that this type of database can be really beneficial for a data warehouse. Furthermore, if you are using a CRM system even then this database mat prove to be of great value. Meanwhile, it is also worth mentioning that even an ad-hoc inquiry system can make the most of this type of database without any difficulty. However, if you plan to use the columnar approach in any of the aforesaid situations then you must ensure that you'll be computing the aggregates over such data items that are similar in nature. 

It is also advisable that you think about using a columnar database instead of a row one only if you are dealing with a large number of data items. Anyways, it is imperative for you to be familiar with the situations where you may consider giving up on a row-oriented database. Firstly, you may give some thought to it if a relatively small subset of all columns of data is involved. If you are wondering how the columnar approach may help you in this situation then you must realize that a smaller subset can obviously be read faster. On the other hand, reading all data can be time consuming and may affect the speed. 

Nevertheless, the good news is that you do not necessarily have to adopt a column-oriented layout to be able to reap the aforesaid benefits. In fact, some of the benefits can be easily achieved even with the aid of a traditional row-oriented database. However, if you are sure that you wish to reap all of the aforesaid benefits then you may have to look for a query execution engine. Furthermore, even the specialization of the storage layer may help you in reaping the benefits to a large extent.