ocaml_mysql: 1.2.1 -> deleted

Quoting from https://github.com/ygrek/ocaml-mysql/blob/b9fa2443082f877897a99c0ed1f752d0721eccff/README

> NB the project is not maintained and likely unsafe to use with OCaml 5, see https://github.com/ygrek/ocaml-mysql/issues/18
>   you probably want to use https://github.com/ocaml-community/ocaml-mariadb instead

ocaml_mysql has no nixpkgs that depend on it.

pkgs/development/ocaml-modules/mysql/default.nix

@@ -1,54 +0,0 @@
-{
-  stdenv,
-  lib,
-  fetchurl,
-  fetchpatch,
-  ocaml,
-  findlib,
-  libmysqlclient,
-}:
-
-# TODO: la versione stabile da' un errore di compilazione dovuto a
-# qualche cambiamento negli header .h
-# TODO: compilazione di moduli dipendenti da zip, ssl, tcl, gtk, gtk2
-
-stdenv.mkDerivation (finalAttrs: {
-  name = "ocaml${ocaml.version}-${finalAttrs.pname}-${finalAttrs.version}";
-  pname = "ocaml-mysql";
-  version = "1.2.1";
-
-  src = fetchurl {
-    url = "http://ygrek.org.ua/p/release/ocaml-mysql/ocaml-mysql-${finalAttrs.version}.tar.gz";
-    sha256 = "06mb2bq7v37wn0lza61917zqgb4bsg1xxb73myjyn88p6khl6yl2";
-  };
-
-  configureFlags = [
-    "--prefix=$out"
-    "--libdir=$out/lib/ocaml/${ocaml.version}/site-lib/mysql"
-  ];
-
-  nativeBuildInputs = [
-    ocaml
-    findlib
-  ];
-
-  createFindlibDestdir = true;
-
-  propagatedBuildInputs = [ libmysqlclient ];
-
-  strictDeps = true;
-
-  patches = [
-    (fetchpatch {
-      url = "https://github.com/ygrek/ocaml-mysql/compare/v1.2.1...d6d1b3b262ae2cf493ef56f1dd7afcf663a70a26.patch";
-      sha256 = "0018s2wcrvbsw9yaqmwq500qmikwffrgdp5xg9b8v7ixhd4gi6hn";
-    })
-  ];
-
-  meta = {
-    homepage = "http://ocaml-mysql.forge.ocamlcore.org";
-    description = "Bindings for interacting with MySQL databases from ocaml";
-    license = lib.licenses.lgpl21Plus;
-    maintainers = [ lib.maintainers.roconnor ];
-  };
-})

pkgs/top-level/ocaml-packages.nix

@@ -1475,8 +1475,6 @@ let
 
         ocaml-monadic = callPackage ../development/ocaml-modules/ocaml-monadic { };
 
-        ocaml_mysql = callPackage ../development/ocaml-modules/mysql { };
-
         ocaml_oasis = callPackage ../development/tools/ocaml/oasis { };
 
         ocaml_pcre = callPackage ../development/ocaml-modules/pcre { };
@@ -2355,6 +2353,7 @@ let
         ocaml-freestanding = throw "ocamlPackages.ocaml-freestanding has been removed due to being broken for more than a year; see RFC 180"; # Added 2026-02-05
         ocaml-vdom = throw "2023-10-09: ocamlPackages.ocaml-vdom was renamed to ocamlPackages.vdom";
         ocaml_lwt = throw "ocamlPackages.ocaml_lwt has been renamed to ocamlPackages.lwt"; # Added 2025-12-05
+        ocaml_mysql = throw "ocamlPackages.ocaml_mysql is not maintained, use ocamlPackages.mariadb instead";
         torch = throw "ocamlPackages.torch has been removed due to being broken for more than a year; see RFC 180"; # Added 2026-02-05
       }
     )).overrideScope