I not an expert on database, so please excuse any gaps in my explanation.
It is basically all the game data that does not change - remains static. For example ship attributes, system names, planet coordinates, etc.
CCP makes it available for download, so that people can use it for the websites and 3rd party software/tools.
You can find a copy of the databases here - someone even converted some of the files to csv which makes it easier:
https://www.fuzzwork.co.uk/dump/latest/
You can find descriptions and some more info here:
https://wiki.eveuniversity.org/Static_Data_Export
It does require some work to use the data, because you have to link data from different files for some of it to make sense.
For example, the materials required for each blueprint is in the file called:
industryActivityMaterials
But it uses TypeID’s (numbers) to identify each item. So you have to look at the file called:
invTypes
The 2nd one gives you the names for each ID, and also has a “Published” attribute (yes/no) that tells you whether the item is ingame, or not.
The 2nd one is also used to find the ID’s for Trit, Pyer, and Mex. Because the 1st table lists the materials using their ID’s, not their names.
Hehe, so as you can see it requires some work.
Also, I should mention this important point: Even if an item has Published=yes it only means it is a valid ingame object. But it does not always mean you can actually get it from the market/contracts/loot. This is where there is some more ingame work that you will have to do to see what can be obtained, and what can’t.