* mysql service would assume that all the `*.sql` files in the directory, provided by `initialDatabases [{ schema = <directory>; … }]`, exists in a folder named [mysql-databases](291e7be83a/nix/mysql.nix (L239-L241)), after this change it would just look for all the `*.sql` files in the top-level schema directory.
* add tests
* clickhouse init script
* clickhouse schema test
* clickhouse folder
* docs: add initialDatabases to tips & tricks
* docs: use heading anchor
* add TODO to find an alternative to start clickhouse-server during init
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Co-authored-by: shivaraj-bh <sbh69840@gmail.com>
* Use psql instead of postgres, as a result, use `pg_ctl` to temporarily start the postgres server in `${name}-init` process.
* Avoid creating a custom `postgresPkg` with extensions by using `apply` attribute provided by `mkOption`
* Refactor setup script, use `writeShellApplication` and resolve shell-check errors
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Co-authored-by: shivaraj-bh <sbh69840@gmail.com>