* guix/config.scm.in (%store-database-directory): New variable. * guix/store/database.scm: New file. * tests/store-database.scm: New file. * Makefile.am (STORE_MODULES): New variable. (MODULES, MODULES_NOT_COMPILED): Adjust accordingly. (SCM_TESTS) [HAVE_GUILE_SQLITE3]: Add tests/store-database.scm. Co-authored-by: Ludovic Courtès <ludo@gnu.org>