Sequel::KeysetPagination

Adds support to Sequel Dataset with both an before and after cursor. Allowing you to slice your dataset in both directions.

Provides cursor support for Relay like pagination: https://facebook.github.io/relay/graphql/connections.htm

To install

# Activate the extension:
Sequel::Database.extension :keyset_pagination
# or
DB.extension :keyset_pagination

Simple pagination example

# Activate the extension:
Sequel::Database.extension :keyset_pagination
# or
DB.extension :keyset_pagination

# Get your first collection of records
DB[:records].order(:id).limit(10)

# Pass the last record's ID as the seek cursor to get the next page
DB[:records].order(:id).limit(5).seek(after: 1125)
# SELECT * FROM `records` WHERE (`id` > 1125) ORDER BY `id` LIMIT 5

Multiple column ordering (example tv episodes)

# To get all episodes after episode 5 of season 1:
DB[:episodes].order(:season_nr, :ep_nr).limit(5).seek(after: [1, 5])
# SELECT * FROM `episodes` WHERE (((`ep_nr` > 5) AND (`season_nr` = 1)) OR (`season_nr` > 1)) ORDER BY `season_nr`, `ep_nr` LIMIT 5

In the above example, both 1x06 up to 1x20 and all future episodes after s02 will be includes in the dataset.

Slicing in both directions

# You can pass both an `after` and `before` cursor to seek
DB[:posts].order(:created_at).seek(before: '2018-10-02T15:00:00Z', after: '2016-10-02T15:00:00Z')
# SELECT * FROM `posts` WHERE ((`created_at` > '2016-10-02T15:00:00Z') AND (`created_at` < '2018-10-02T15:00:00Z')) ORDER BY `created_at`

This will slice your dataset between those two cursors. An unlimited amount of sort columns are supported.