5.40.0.txt

doc/release_notes/5.40.0.txt
Last Update: 2020-12-31 11:06:03 -0800

New Features

  • On SQLite 3.33.0+, the UPDATE FROM syntax is now supported. This allows you to update one table based on a join to another table. The SQLite syntax is based on the PostgreSQL syntax, and the Sequel API is the same for both. You need to pass multiple tables to Dataset#from. The first table is the table to update, and the remaining tables are used to construct the UPDATE FROM clause:

    DB[:a, :b].where{{a[:c]=>b[:d]}}.update(:e=>'f')
    # UPDATE a SET e = 'f' FROM b WHERE (a.c = b.d)

    Unlike PostgreSQL, SQLite does not support the deletion of joined datasets. Related to this, the following methods for testing database support for modifying joined datasets have been added:

    • supports_updating_joins?

    • supports_deleting_joins?

Other Improvements

  • The pg_interval and date_arithmetic extensions now support ActiveSupport 6.1.

  • Sequel no longer issues method redefinition warnings in verbose mode. As Ruby 3 has dropped uninitialized instance variable warnings, Sequel is now verbose warning free on Ruby 3.

Backwards Compatibility

  • Trying to truncate or insert into a joined dataset now correctly raises an exception even if the joined dataset supports updates.

  • The private Dataset#check_modification_allowed! method is now deprecated, and users (custom adapters) should now switch to one of the more specific methods introduced in this version:

    • check_insert_allowed!

    • check_update_allowed!

    • check_delete_allowed!