Your original TIME ZONE value on PostgreSQL is correctly restored now…

…, after going through options :utc and then going back to :local

[rails#4950 state:committed]

Signed-off-by: José Valim <jose.valim@gmail.com>

activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb

@@ -216,7 +216,10 @@ def initialize(connection, logger, connection_parameters, config)
         super(connection, logger)
         @connection_parameters, @config = connection_parameters, config
 
+        # @local_tz is initialized as nil to avoid warnings when connect tries to use it
+        @local_tz = nil
         connect
+        @local_tz = execute('SHOW TIME ZONE').first["TimeZone"]
       end
 
       # Is this connection alive and ready for queries?
@@ -929,9 +932,8 @@ def configure_connection
           # TIMESTAMP WITH ZONE types in UTC.
           if ActiveRecord::Base.default_timezone == :utc
             execute("SET time zone 'UTC'")
-          else
-            offset = Time.local(2000).utc_offset / 3600
-            execute("SET time zone '#{offset}'")
+          elsif @local_tz
+            execute("SET time zone '#{@local_tz}'")
           end
         end