MySQL: speedup date/time parsing.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@7769 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

3 files changed, 96 insertions, 58 deletions

diff --git a/activerecord/CHANGELOG b/activerecord/CHANGELOG
index 689575c2c6..391c1273f3 100644
--- a/activerecord/CHANGELOG
+++ b/activerecord/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* MySQL: speedup date/time parsing.  [Jeremy Kemper]
+
 * Fix calling .clear on a has_many :dependent=>:delete_all association. [tarmo]
 
 * Allow change_column to set NOT NULL in the PostgreSQL adapter [tarmo]
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
index d4143cee3c..b98a493a18 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
@@ -92,76 +92,82 @@ module ActiveRecord
         Base.human_attribute_name(@name)
       end
 
-      # Used to convert from Strings to BLOBs
-      def self.string_to_binary(value)
-        value
-      end
+      class << self
+        # Used to convert from Strings to BLOBs
+        def string_to_binary(value)
+          value
+        end
 
-      # Used to convert from BLOBs to Strings
-      def self.binary_to_string(value)
-        value
-      end
+        # Used to convert from BLOBs to Strings
+        def binary_to_string(value)
+          value
+        end
 
-      def self.string_to_date(string)
-        return string unless string.is_a?(String)
-        date_array = ParseDate.parsedate(string)
-        # treat 0000-00-00 as nil
-        Date.new(date_array[0], date_array[1], date_array[2]) rescue nil
-      end
+        def string_to_date(string)
+          return string unless string.is_a?(String)
+          new_date *ParseDate.parsedate(string)[0..2]
+        end
 
-      def self.string_to_time(string)
-        return string unless string.is_a?(String)
-        time_hash = Date._parse(string)
-        time_hash[:sec_fraction] = microseconds(time_hash)
-        time_array = time_hash.values_at(:year, :mon, :mday, :hour, :min, :sec, :sec_fraction)
-        # treat 0000-00-00 00:00:00 as nil
-        begin
-          Time.send(Base.default_timezone, *time_array)
-        rescue
-          zone_offset = if Base.default_timezone == :local then DateTime.now.offset else 0 end
-          # Append zero calendar reform start to account for dates skipped by calendar reform
-          DateTime.new(*time_array[0..5] << zone_offset << 0) rescue nil
+        def string_to_time(string)
+          return string unless string.is_a?(String)
+          return nil if string.empty?
+          time_hash = Date._parse(string)
+          time_hash[:sec_fraction] = microseconds(time_hash)
+          new_time *time_hash.values_at(:year, :mon, :mday, :hour, :min, :sec, :sec_fraction)
         end
-      end
 
-      def self.string_to_dummy_time(string)
-        return string unless string.is_a?(String)
-        return nil if string.empty?
-        time_hash = Date._parse(string)
-        time_hash[:sec_fraction] = microseconds(time_hash)
-        # pad the resulting array with dummy date information
-        time_array = [2000, 1, 1]
-        time_array += time_hash.values_at(:hour, :min, :sec, :sec_fraction)
-        Time.send(Base.default_timezone, *time_array) rescue nil
-      end
+        def string_to_dummy_time(string)
+          return string unless string.is_a?(String)
+          return nil if string.empty?
 
-      # convert something to a boolean
-      def self.value_to_boolean(value)
-        if value == true || value == false
-          value
-        else
-          %w(true t 1).include?(value.to_s.downcase)
+          string_to_time "2000-01-01 #{string}"
         end
-      end
 
-      # convert something to a BigDecimal
-      def self.value_to_decimal(value)
-        if value.is_a?(BigDecimal)
-          value
-        elsif value.respond_to?(:to_d)
-          value.to_d
-        else
-          value.to_s.to_d
+        # convert something to a boolean
+        def value_to_boolean(value)
+          if value == true || value == false
+            value
+          else
+            %w(true t 1).include?(value.to_s.downcase)
+          end
         end
-      end
 
-      private
-        # '0.123456' -> 123456
-        # '1.123456' -> 123456
-        def self.microseconds(time)
-          ((time[:sec_fraction].to_f % 1) * 1_000_000).to_i
+        # convert something to a BigDecimal
+        def value_to_decimal(value)
+          if value.is_a?(BigDecimal)
+            value
+          elsif value.respond_to?(:to_d)
+            value.to_d
+          else
+            value.to_s.to_d
+          end
         end
 
+        protected
+          # '0.123456' -> 123456
+          # '1.123456' -> 123456
+          def microseconds(time)
+            ((time[:sec_fraction].to_f % 1) * 1_000_000).to_i
+          end
+
+          def new_date(year, mon, mday)
+            Date.new(year, mon, mday) unless year == 0
+          end
+
+          def new_time(year, mon, mday, hour, min, sec, microsec)
+            # Treat 0000-00-00 00:00:00 as nil.
+            return nil if year == 0
+
+            Time.send(Base.default_timezone, year, mon, mday, hour, min, sec, microsec)
+          # Over/underflow to DateTime
+          rescue ArgumentError, TypeError
+            zone_offset = if Base.default_timezone == :local then DateTime.now.offset else 0 end
+            # Append zero calendar reform start to account for dates skipped by calendar reform
+            DateTime.new(year, mon, mday, hour, min, sec, zone_offset, 0)
+          end
+      end
+
+      private
         def extract_limit(sql_type)
           $1.to_i if sql_type =~ /\((.*)\)/
         end
diff --git a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
index c73028aca4..94ec5cf595 100755
--- a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
@@ -94,6 +94,11 @@ module ActiveRecord
       TYPES_DISALLOWING_DEFAULT = Set.new([:binary, :text])
       TYPES_ALLOWING_EMPTY_STRING_DEFAULT = Set.new([:string])
 
+      module Format
+        DATE = /\A(\d{4})-(\d\d)-(\d\d)\z/
+        DATETIME = /\A(\d{4})-(\d\d)-(\d\d) (\d\d):(\d\d):(\d\d)(?:\.(\d{6}))?\z/
+      end
+
       def initialize(name, default, sql_type = nil, null = true)
         @original_default = default
         super
@@ -101,6 +106,31 @@ module ActiveRecord
         @default = '' if @original_default == '' && no_default_allowed?
       end
 
+      class << self
+        def string_to_date(string)
+          return string unless string.is_a?(String)
+          return nil if string.empty?
+
+          if string =~ Format::DATE
+            new_date $1.to_i, $2.to_i, $3.to_i
+          else
+            new_date *ParseDate.parsedate(string)[0..2]
+          end
+        end
+
+        def string_to_time(string)
+          return string unless string.is_a?(String)
+          return nil if string.empty?
+
+          if string =~ Format::DATETIME
+            new_time $1.to_i, $2.to_i, $3.to_i, $4.to_i, $5.to_i, $6.to_i, $7.to_i
+          else
+            time_hash = Date._parse(string)
+            new_time *(time_hash.values_at(:year, :mon, :mday, :hour, :min, :sec) << microseconds(time_hash))
+          end
+        end
+      end
+
       private
         def simplified_type(field_type)
           return :boolean if MysqlAdapter.emulate_booleans && field_type.downcase.index("tinyint(1)")