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.
Modifying the attribute table
Removing columns
In the first example, let's delete some values from our administrative boundaries layer. If we inspect its attribute table, we can see some unnecessary columns. In my table, ID_0 and CCN_1 have constant values, which have...