Hither Specification

Hither is a general purpose database munging tool.

Overview

Hither's primary goals are:

• Provide a CLI command called hither

• RDBMS schema and database migration

• Provide a schema data definition language

• Programming language agnostic

• Database framework agnostic

• Schema definition diffing

• Generate database files from definitions

  • DB schema files

  • DB migration files

• Generate database code from definitions

  • DBIx::Class classes for Perl

  • ActiveRecord classes for Ruby

Hither Command Actions

The hither command has many actions. Here are some examples:

hither migrate <options> <arguments>

Migrate a database from state A to state B.

hither import …

Import a database from a source. Could be a dump or another database.

hither generate …

Generate things from things.

hither diff …

Implementation Strategy

Hither will start out as a wrapper around other tools. It will patch and fill in gaps as necessary.

For starters, heavy use will be made of:

SQL::Translator

This module does a lot of transformations. It is a good starting point.

Databases of Focus

Eventually all popular, open source databases should be supported. For now just concentrating on 3 for bootstrapping phase. Having 3 concerns is a good number for agnostic, yet focused, projects.

PostgreSQL

This DB is driving the need for this tool currently.

SQLite

Simple, single file, real database. Good for prototyping and testing.

CSV

CSV is considered a database since so much open data is in this format.