BREAKING CHANGE: the TruncateProcessor will now RESTART IDENTITY when…

… using postgres - this behaviour can be changed by passing :options => 'CONTINUE IDENTITY'

CHANGELOG

@@ -1,4 +1,5 @@
 0.9.5 - unreleased
+* BREAKING CHANGE: the TruncateProcessor will now RESTART IDENTITY when using postgres - this behaviour can be changed by passing :options => 'CONTINUE IDENTITY' (thbar)
 * New EnsureFieldsPresenceProcessor (thbar)
 * New CsvDestination based on FasterCSV (lgustafson)
 * Fix #41: Allow cache to be turned off on ForeignKeyLookupTransform

lib/etl/processor/truncate_processor.rb

@@ -14,16 +14,21 @@ class TruncateProcessor < ETL::Processor::Processor
       # Options:
       # * <tt>:target</tt>: The target connection
       # * <tt>:table</tt>: The table name
+      # * <tt>:options</tt>: Optional truncate options
       def initialize(control, configuration)
         super
         #@file = File.join(File.dirname(control.file), configuration[:file])
         @target = configuration[:target] || {}
         @table = configuration[:table]
+        @options = configuration[:options] 
       end
 
       def process
         conn = ETL::Engine.connection(target)
-        conn.truncate(table_name)
+        if conn.is_a?(ActiveRecord::ConnectionAdapters::PostgreSQLAdapter)
+          @options ||= 'RESTART IDENTITY'
+        end
+        conn.truncate(table_name, @options)
       end
 
       private

test/connection/mysql/schema.sql

@@ -29,6 +29,7 @@ create table person_dimension (
 
 drop table if exists truncate_test;
 create table truncate_test (
+  id int not null primary key auto_increment,
 	x char(4)
 );
 insert into truncate_test (x) values ('a');

test/connection/postgresql/schema.sql

@@ -32,6 +32,7 @@ create table person_dimension (
 
 drop table truncate_test;
 create table truncate_test (
+  id SERIAL PRIMARY KEY,
 	x character varying(4)
 );
 insert into truncate_test (x) values ('a');

test/truncate_processor_test.rb

@@ -0,0 +1,37 @@
+require File.dirname(__FILE__) + '/test_helper'
+
+include ETL::Processor
+
+class TruncateTest < ActiveRecord::Base
+  set_table_name 'truncate_test'
+end
+
+class TruncateProcessorTest < Test::Unit::TestCase
+
+  def create_item!
+    TruncateTest.create!(:x => 'ABC')
+  end
+
+  def truncate!(options=nil)
+    TruncateProcessor.new(nil,
+      :target => :data_warehouse,
+      :table => TruncateTest.table_name,
+      :options => options
+      ).process
+  end
+
+  should 'reset ids by default' do
+    create_item!
+    truncate!
+    assert_equal 1, create_item!.id
+  end
+
+  if ETL::Engine.connection(:data_warehouse).class.name =~ /postgres/i
+    should 'allow disabling id reset for postgres' do
+      truncate!
+      create_item!
+      truncate!('CONTINUE IDENTITY')
+      assert_equal 2, create_item!.id
+    end
+  end
+end