Viewr

Viewr provides for a generic description format for SQL views and functions, and creates or drops them, resolving dependencies on the way.

It currently has a dependency on Sequel for accessing the database to create SQL views and only works with PostgreSQL databases.

Installation

Add this line to your application's Gemfile, adjusting the version number as wanted:

gem 'viewr', github: 'mindmatters/viewr', tag: 'v0.0.6'

and then execute:

$ bundle install

Usage

Place YAML Files containing descriptions of your views and functions into two folder, e.g. db/views and db/functions in a Rails project.

Example YAML file:

name: view_name
dependencies:
    - some_other_view
    - some_function
sql: |
    SELECT * FROM my_fancy_table

This file describes an SQL view view_name which depends on some_other_view and some_function. When Viewr creates view_name, it will do so only after it has created some_other_view and some_function, possibly creating other views or functions these depend on.

To create or drop views and functions, you first need to:

    require 'viewr'

To issue CREATE statements for all defined views and functions,

    Viewr.create_all(sequel_database_object, '/path/to/view/files', '/path/to/function/files')

To drop all views and functions,

    Viewr.drop_all(sequel_database_object, '/path/to/view/files', '/path/to/function/files')

To drop all views and functions and then re-create them,

    Viewr.recreate_all(sequel_database_object, '/path/to/view/files', '/path/to/function/files')

It makes sense to define rake tasks which execute these statements.

Contributing

Pull requests are warmly welcome! :)