The comparison was vs keeping stuff in a hash table in memory, and I was saying databases are no worse.
But that's clearly not true. In the most extreme case, that hash table is referenced simply by a variable in your program - it's already in your program's address-space! There's no way a database can come close to that.
Not to mention that you can hash arbitrary objects in a hash table with no mapping of any kind.
hash at: key put: anObject
Databases are vastly more complicated and require me to completely disassembly the object graph anObject may contain into a set of tables and rows to store it, and then reassemble the graph from tables and rows back into their object form when fetching.
The second one commits to using a relational database, one often easily triples the size of the code base. There's nothing simple about that.
But that's clearly not true. In the most extreme case, that hash table is referenced simply by a variable in your program - it's already in your program's address-space! There's no way a database can come close to that.