Module | ::PostgreSQL |
In: |
lib/jdbc_adapter/jdbc_postgre.rb
|
ORDER BY clause for the passed order option.
PostgreSQL does not allow arbitrary ordering when using DISTINCT ON, so we work around this by wrapping the sql as a sub-select and ordering in that query.
SELECT DISTINCT clause for a given set of columns and a given ORDER BY clause.
PostgreSQL requires the ORDER BY columns in the select list for distinct queries, and requires that the ORDER BY include the distinct column.
distinct("posts.id", "posts.created_at desc")
Returns the configured supported identifier length supported by PostgreSQL, or report the default of 63 on PostgreSQL 7.x.