diff --git a/misc/plugin/category.rb b/misc/plugin/category.rb
index b0ce89d8..3cc0109a 100644
--- a/misc/plugin/category.rb
+++ b/misc/plugin/category.rb
@@ -488,16 +488,24 @@ def recreate(years)
 		cgi = Category::CGI::new
 
 		list = []
-		years.each do |y, ms|
-			ms.each do |m|
-				ym = "#{y}#{m}"
-				cgi.params['date'] = [ym]
-				m = TDiaryMonth.new(cgi, '', @conf)
-				m.diaries.each do |ymd, diary|
-					next if !diary.visible?
-					initial_replace_sections(diary)
-					diary.each_section do |s|
-						list |= s.categories unless s.categories.empty?
+		@plugin.__send__(:transaction, 'category') do |db|
+			db.keys.each {|key|db.delete(key)}
+
+			years.each do |y, ms|
+				ms.each do |m|
+					ym = "#{y}#{m}"
+					cgi.params['date'] = [ym]
+					m = TDiaryMonth.new(cgi, '', @conf)
+					m.diaries.each do |ymd, diary|
+						next if !diary.visible? or !diary.categorizable?
+						categorized = categorize_diary(diary)
+						categorized.keys.each do |c|
+							cat = get(db, c) || {}
+							set(db, c, cat.update(categorized[c]))
+						end
+						diary.each_section do |s|
+							list |= s.categories unless s.categories.empty?
+						end
 					end
 				end
 			end
@@ -582,22 +590,6 @@ def categorize_diary(diary)
 
 		categorized
 	end
-
-	#
-	# cache each section of diary
-	# used in recreate
-	#
-	def initial_replace_sections(diary)
-		return if diary.nil? or !diary.visible? or !diary.categorizable?
-
-		categorized = categorize_diary(diary)
-		@plugin.__send__(:transaction, 'category') do |db|
-			categorized.keys.each do |c|
-				cat = get(db, c) || {}
-				set(db, c, cat.update(categorized[c]))
-			end
-		end
-	end
 end
 
 end # module Category