The thing is that a database already stores data but all the schematics and ddl stuff would be much more conveniently kept in descriptive plaintext.
This makes SQL needlessly complex and tools to work with schemas far more complicated than they actually have to be.
In Lisp, most things are a list/pair. In SQL, most things should have been a table.
insert into schema.users (type, name, columns) values ('btree_index', 'index_dob', 'dob DESC, name ASC')The DDL is also implementation specific but there’s a much higher degree of practical commonality. When writing application db migrations, and especially when supporting multiple backend databases, I’d definitely rather compose/generate DDL than engage with the minutiae of each.
Even table names, column names and domain names are represented as character strings in some tables. Tables containing such names are normally part of the built-in system catalog. The catalog is accordingly a relational data base itself — one that is dynamic and active and represents the metadata (data describing the rest of the data in the system)
[1] The Twelve Rules, E.F.Codd https://reldb.org/c/index.php/twelve-rules/