The #recutils #database #Emacs mode. I haven’t tried it but it sounds horrible
on 02016-07-07A database that stores stuff in a text file; the format is (almost) blank-line-separated RFC-822 headers. “#Recutils is a set of tools and libraries to access human-editable, plain text #databases called recfiles. The data is stored as a sequence of records, each record containing an arbitrary number of named fields.”. recsel -e "Age < 18" -P Name acquaintances.rec to select names; recins -f Name -v "Mr Foo" -f Email -v foo@bar.baz contacts.rec to insert. There’s an Emacs mode, but it’s not part of standard Emacs (or very powerful, I think), and there seem to be some problems in the interface. Supports some minimal integrity constraints including range checks, uniqueness, and regexps, but not referential integrity (foreign key constraints). Supports references to other records via a primary key with an ad-hoc convention for fields thus obtained, but not arbitrary joins. Has its own mail-merge template syntax for reports.