We can not only use the attribute tables of layers, but we can also extend, decrease, or modify them. These are very useful functions for maintaining a layer. For example, as data often comes in a general format with a lot of obsolete attributes, which is practically useless for our analysis, we can get rid of it in a matter of clicks. The size of the attribute table always has an impact on performance; therefore, it is beneficial to not store superfluous data.