Fixed dumping from postgresql columns in index in wrong order. [#2515 …

…state:resolved]

Signed-off-by: Tarmo Tänav <tarmo@itech.ee>

activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb

@@ -640,33 +640,36 @@ def tables(name = nil)
       def indexes(table_name, name = nil)
          schemas = schema_search_path.split(/,/).map { |p| quote(p) }.join(',')
          result = query(<<-SQL, name)
-           SELECT distinct i.relname, d.indisunique, a.attname
-             FROM pg_class t, pg_class i, pg_index d, pg_attribute a
+           SELECT distinct i.relname, d.indisunique, d.indkey, t.oid
+             FROM pg_class t, pg_class i, pg_index d
            WHERE i.relkind = 'i'
              AND d.indexrelid = i.oid
              AND d.indisprimary = 'f'
              AND t.oid = d.indrelid
              AND t.relname = '#{table_name}'
              AND i.relnamespace IN (SELECT oid FROM pg_namespace WHERE nspname IN (#{schemas}) )
-             AND a.attrelid = t.oid
-             AND ( d.indkey[0]=a.attnum OR d.indkey[1]=a.attnum
-                OR d.indkey[2]=a.attnum OR d.indkey[3]=a.attnum
-                OR d.indkey[4]=a.attnum OR d.indkey[5]=a.attnum
-                OR d.indkey[6]=a.attnum OR d.indkey[7]=a.attnum
-                OR d.indkey[8]=a.attnum OR d.indkey[9]=a.attnum )
           ORDER BY i.relname
         SQL
 
-        current_index = nil
+
         indexes = []
 
-        result.each do |row|
-          if current_index != row[0]
-            indexes << IndexDefinition.new(table_name, row[0], row[1] == "t", [])
-            current_index = row[0]
-          end
+        indexes = result.map do |row|
+          index_name = row[0]
+          unique = row[1] == 't'
+          indkey = row[2].split(" ")
+          oid = row[3]
+
+          columns = query(<<-SQL, "Columns for index #{row[0]} on #{table_name}").inject({}) {|attlist, r| attlist[r[1]] = r[0]; attlist}
+          SELECT a.attname, a.attnum
+          FROM pg_attribute a
+          WHERE a.attrelid = #{oid}
+          AND a.attnum IN (#{indkey.join(",")})
+          SQL
+
+          column_names = indkey.map {|attnum| columns[attnum] }
+          IndexDefinition.new(table_name, index_name, unique, column_names)
 
-          indexes.last.columns << row[2]
         end
 
         indexes

activerecord/test/cases/schema_dumper_test.rb

@@ -152,6 +152,11 @@ def test_schema_dump_illegal_ignored_table_value
     end
   end
 
+  def test_schema_dumps_index_columns_in_right_order
+    index_definition = standard_dump.split(/\n/).grep(/add_index.*companies/).first.strip
+    assert_equal 'add_index "companies", ["firm_id", "type", "rating", "ruby_type"], :name => "company_index"', index_definition
+  end
+
   if current_adapter?(:MysqlAdapter)
     def test_schema_dump_should_not_add_default_value_for_mysql_text_field
       output = standard_dump

activerecord/test/schema/schema.rb

@@ -118,6 +118,8 @@ def create_table(*args, &block)
     t.integer :rating, :default => 1
   end
 
+  add_index :companies, [:firm_id, :type, :rating, :ruby_type], :name => "company_index"
+
   create_table :computers, :force => true do |t|
     t.integer :developer, :null => false
     t.integer :extendedWarranty, :null => false