I'm using a tree-sitter grammar^1, which category the OP doesn't mention, to index database object references in data access code and process schema migrations^2. The idea is early detection of potentially-dangerous database changes that modify or drop tables/views still used elsewhere, across the entire organization's code. It's already saved my bacon a few times.
^1 specifically https://github.com/DerekStride/tree-sitter-sql , but there are a few others around too
^2 https://ectomigo.com