ActiveRecord ConnectionAdapters ConnectionPool #spec attribute spec Ruby on Rails 3.1.12 Since v2.2.3 Last seen in v6.0.6 Available in: v2.2.3 v2.3.18 v3.0.20 v3.1.12 v3.2.22.5 v4.0.13 v4.1.16 v4.2.9 v5.2.8.1 v6.0.6 Compare with: … v2.2.3 v2.3.18 v3.0.20 v3.2.22.5 v4.0.13 v4.1.16 v4.2.9 v5.2.8.1 v6.0.6 No documentation comment.
