2 files changed, 18 insertions, 3 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
index 9b74c3a10f..dc5b305843 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
@@ -849,6 +849,21 @@ module ActiveRecord
 
         remove_connection(spec.name)
         owner_to_pool[spec.name] = ConnectionAdapters::ConnectionPool.new(spec)
+
+        message_bus = ActiveSupport::Notifications.instrumenter
+        payload = {
+          connection_id: object_id
+        }
+        if spec
+          payload[:spec_name] = spec.name
+          payload[:config] = spec.config
+        end
+
+        message_bus.instrument('!connection.active_record', payload) do
+          owner_to_pool[spec.name] = ConnectionAdapters::ConnectionPool.new(spec)
+        end
+
+        owner_to_pool[spec.name]
       end
 
       # Returns true if there are any active connections among the connection
@@ -881,7 +896,7 @@ module ActiveRecord
       # for (not necessarily the current class).
       def retrieve_connection(spec_name) #:nodoc:
         pool = retrieve_connection_pool(spec_name)
-        raise ConnectionNotEstablished, "No connection pool with id '#{spec_name}' found." unless pool
+        raise ConnectionNotEstablished, "No connection pool with '#{spec_name}' found." unless pool
         conn = pool.connection
         raise ConnectionNotEstablished, "No connection for '#{spec_name}' in connection pool" unless conn
         conn
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
index 396cb0b07a..9e9ace49db 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
@@ -998,8 +998,8 @@ module ActiveRecord
         sm_table = ActiveRecord::Migrator.schema_migrations_table_name
 
         if supports_multi_insert?
-          sql = "INSERT INTO #{sm_table} (version) VALUES "
-          sql << versions.map {|v| "('#{v}')" }.join(', ')
+          sql = "INSERT INTO #{sm_table} (version) VALUES\n"
+          sql << versions.map {|v| "('#{v}')" }.join(",\n")
           sql << ";\n\n"
           sql
         else