New #lowercase_schema_reflection configuration that allows you to downcase all tables and columns. Good for legacy databases. Fixes #86. Thanks @dmajkic.

Author: metaskills

CHANGELOG

@@ -1,6 +1,9 @@
 
 * 3.1.0.rc *
 
+* New #lowercase_schema_reflection configuration that allows you to downcase all tables and columns.
+  Good for legacy databases. Fixes #86. Thanks @dmajkic.
+
 * Rails 3.1 with prepared statement support. Uses "EXEC sp_executesql ..." for just about everything now.
 
 

README.rdoc

@@ -7,6 +7,7 @@ The SQL Server adapter for ActiveRecord.
 == What's New
 
 * Rails 3.1 prepared statement support leverages cached query plans.
+* New #lowercase_schema_reflection configuration option for legacy DBs.
 * New dblib connection mode using TinyTds!
 
 
@@ -88,7 +89,14 @@ By default the adapter will use non-unicode safe data types for :string and :tex
 It is important to remember that unicode types in SQL Server have approximately half the storage capacity as their counter parts. So where a normal string would max out at (8000) a unicode string will top off at (4000).
 
 
-====  Schema Information Logging
+==== Force Schema To Lowercase
+
+Although it is not necessary, the Ruby convention is to use lowercase method names. If your database schema is in upper or mixed case, we can force all table and column names during the schema reflection process to be lowercase. Add this to your config/initializers file for the adapter.
+
+  ActiveRecord::ConnectionAdapters::SQLServerAdapter.lowercase_schema_reflection = true
+
+
+==== Schema Information Logging
 
 By default all queries to the INFORMATION_SCHEMA table is silenced. If you think logging these queries are useful, you can enable it by adding this like to a initializer file.
 

lib/active_record/connection_adapters/sqlserver/database_statements.rb

@@ -325,13 +325,14 @@ def handle_to_names_and_values_dblib(handle, options={})
             qo[:as] = (options[:ar_result] || options[:fetch] == :rows) ? :array : :hash
           end
           results = handle.each(query_options)
-          options[:ar_result] ? ActiveRecord::Result.new(handle.fields, results) : results
+          columns = lowercase_schema_reflection ? handle.fields.map { |c| c.downcase } : handle.fields
+          options[:ar_result] ? ActiveRecord::Result.new(columns, results) : results
         end
 
         def handle_to_names_and_values_odbc(handle, options={})
           @connection.use_utc = ActiveRecord::Base.default_timezone == :utc
           if options[:ar_result]
-            columns = handle.columns(true).map { |c| c.name }
+            columns = lowercase_schema_reflection ? handle.columns(true).map { |c| c.name.downcase } : handle.columns(true).map { |c| c.name }
             rows = handle.fetch_all || []
             ActiveRecord::Result.new(columns, rows)
           else

lib/active_record/connection_adapters/sqlserver/schema_statements.rb

@@ -9,7 +9,7 @@ def native_database_types
 
         def tables(name = nil)
           info_schema_query do
-            select_values "SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_NAME <> 'dtproperties' AND TABLE_SCHEMA = schema_name()"
+            select_values "SELECT #{lowercase_schema_reflection_sql('TABLE_NAME')} FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_NAME <> 'dtproperties' AND TABLE_SCHEMA = schema_name()"
           end
         end
 
@@ -118,7 +118,7 @@ def change_column_null(table_name, column_name, null, default = nil)
 
         def views(name = nil)
           @sqlserver_views_cache ||= 
-            info_schema_query { select_values("SELECT TABLE_NAME FROM INFORMATION_SCHEMA.VIEWS WHERE TABLE_NAME NOT IN ('sysconstraints','syssegments')") }
+            info_schema_query { select_values("SELECT #{lowercase_schema_reflection_sql('TABLE_NAME')} FROM INFORMATION_SCHEMA.VIEWS WHERE TABLE_NAME NOT IN ('sysconstraints','syssegments')") }
         end
 
 
@@ -158,24 +158,24 @@ def column_definitions(table_name)
           table_name = unqualify_table_name(table_name)
           sql = %{
             SELECT
-            columns.TABLE_NAME as table_name,
-            columns.COLUMN_NAME as name,
-            columns.DATA_TYPE as type,
-            columns.COLUMN_DEFAULT as default_value,
-            columns.NUMERIC_SCALE as numeric_scale,
-            columns.NUMERIC_PRECISION as numeric_precision,
+            #{lowercase_schema_reflection_sql('columns.TABLE_NAME')} AS table_name,
+            #{lowercase_schema_reflection_sql('columns.COLUMN_NAME')} AS name,
+            columns.DATA_TYPE AS type,
+            columns.COLUMN_DEFAULT AS default_value,
+            columns.NUMERIC_SCALE AS numeric_scale,
+            columns.NUMERIC_PRECISION AS numeric_precision,
             CASE
               WHEN columns.DATA_TYPE IN ('nchar','nvarchar') THEN columns.CHARACTER_MAXIMUM_LENGTH
               ELSE COL_LENGTH(columns.TABLE_SCHEMA+'.'+columns.TABLE_NAME, columns.COLUMN_NAME)
-            END as length,
+            END AS length,
             CASE
               WHEN columns.IS_NULLABLE = 'YES' THEN 1
               ELSE NULL
-            END as is_nullable,
+            END AS is_nullable,
             CASE
               WHEN COLUMNPROPERTY(OBJECT_ID(columns.TABLE_SCHEMA+'.'+columns.TABLE_NAME), columns.COLUMN_NAME, 'IsIdentity') = 0 THEN NULL
               ELSE 1
-            END as is_identity
+            END AS is_identity
             FROM #{db_name_with_period}INFORMATION_SCHEMA.COLUMNS columns
             WHERE columns.TABLE_NAME = @0
               AND columns.TABLE_SCHEMA = #{table_schema.blank? ? "schema_name()" : "@1"}
@@ -279,6 +279,10 @@ def detect_column_for!(table_name, column_name)
           column
         end
 
+        def lowercase_schema_reflection_sql(node)
+          lowercase_schema_reflection ? "LOWER(#{node})" : node
+        end
+        
         # === SQLServer Specific (View Reflection) ====================== #
 
         def view_table_name(table_name)
@@ -313,14 +317,13 @@ def table_name_or_views_table_name(table_name)
 
         def views_real_column_name(table_name,column_name)
           view_definition = view_information(table_name)[:VIEW_DEFINITION]
-          
           match_data = view_definition.match(/([\w-]*)\s+as\s+#{column_name}/im)
           match_data ? match_data[1] : column_name
         end
 
         # === SQLServer Specific (Column/View Caches) =================== #
 
-        def initialize_sqlserver_caches(reset_columns=true)
+        def initialize_sqlserver_caches
           @sqlserver_views_cache = nil
           @sqlserver_view_information_cache = {}
           @sqlserver_quoted_column_and_table_names = {}

lib/active_record/connection_adapters/sqlserver_adapter.rb

@@ -165,12 +165,11 @@ class SQLServerAdapter < AbstractAdapter
       DATABASE_VERSION_REGEXP     = /Microsoft SQL Server\s+"?(\d{4}|\w+)"?/
       SUPPORTED_VERSIONS          = [2005,2008,2010,2011].freeze
 
-      attr_reader :database_version, :database_year,
-                  :connection_supports_native_types
+      attr_reader :database_version, :database_year
 
       cattr_accessor :native_text_database_type, :native_binary_database_type, :native_string_database_type,
                      :log_info_schema_queries, :enable_default_unicode_types, :auto_connect,
-                     :cs_equality_operator
+                     :cs_equality_operator, :lowercase_schema_reflection
 
       def initialize(logger,config)
         @connection_options = config
@@ -263,8 +262,7 @@ def reset!
       end
 
       def clear_cache!
-        # This requires db admin perms and I'm not even sure it is a good idea.
-        # raw_connection_do "DBCC FREEPROCCACHE WITH NO_INFOMSGS" rescue nil
+        initialize_sqlserver_caches
       end
 
       # === Abstract Adapter (Misc Support) =========================== #

test/cases/adapter_test_sqlserver.rb

@@ -79,7 +79,7 @@ def setup
     end
 
     context 'for #unqualify_table_name and #unqualify_db_name' do
-
+    
       setup do
         @expected_table_name = 'baz'
         @expected_db_name = 'foo'
@@ -110,7 +110,7 @@ def setup
             "This qualifed_table_name #{qtn} did not unqualify the db_name correctly."
         end
       end
-
+    
     end
 
     should 'return true to #insert_sql? for inserts only' do
@@ -121,32 +121,32 @@ def setup
     end
 
     context 'for #get_table_name' do
-
+    
       should 'return quoted table name from basic INSERT, UPDATE and SELECT statements' do
         assert_equal '[funny_jokes]', @connection.send(:get_table_name,@basic_insert_sql)
         assert_equal '[customers]', @connection.send(:get_table_name,@basic_update_sql)
         assert_equal '[customers]', @connection.send(:get_table_name,@basic_select_sql)
       end
-
+    
     end
 
     context 'with different language' do
-
+    
       teardown do
         @connection.execute("SET LANGUAGE us_english") rescue nil
       end
-
+    
       should_eventually 'do a date insertion when language is german' do
         @connection.execute("SET LANGUAGE deutsch")
         assert_nothing_raised do
           Task.create(:starting => Time.utc(2000, 1, 31, 5, 42, 0), :ending => Date.new(2006, 12, 31))
         end
       end
-
+    
     end
 
     context 'testing #enable_default_unicode_types configuration' do
-
+    
       should 'use non-unicode types when set to false' do
         with_enable_default_unicode_types(false) do
           assert_equal 'varchar', @connection.native_string_database_type
@@ -160,9 +160,38 @@ def setup
           assert_equal 'nvarchar(max)', @connection.native_text_database_type
         end
       end
-
+    
     end
 
+    context 'testing #lowercase_schema_reflection' do
+
+      setup do
+        UpperTestDefault.delete_all
+        UpperTestDefault.create :COLUMN1 => 'Got a minute?', :COLUMN2 => 419
+        UpperTestDefault.create :COLUMN1 => 'Favorite number?', :COLUMN2 => 69
+      end
+      
+      teardown do
+        @connection.lowercase_schema_reflection = false
+      end
+
+      should 'not lowercase schema reflection by default' do
+        assert UpperTestDefault.columns_hash['COLUMN1']
+        assert_equal 'Got a minute?', UpperTestDefault.first.COLUMN1
+        assert_equal 'Favorite number?', UpperTestDefault.last.COLUMN1
+        assert UpperTestDefault.columns_hash['COLUMN2']
+      end
+      
+      should 'lowercase schema reflection when set' do
+        @connection.lowercase_schema_reflection = true
+        UpperTestLowered.reset_column_information
+        assert UpperTestLowered.columns_hash['column1']
+        assert_equal 'Got a minute?', UpperTestLowered.first.column1
+        assert_equal 'Favorite number?', UpperTestLowered.last.column1
+        assert UpperTestLowered.columns_hash['column2']
+      end
+
+    end
 
   end
 
@@ -187,23 +216,23 @@ def setup
       end
 
       context 'finding existing DB objects' do
-
+  
         should 'find 003 millisecond in the DB with before and after casting' do
           existing_003 = SqlServerChronic.find_by_datetime!(@db_datetime_003)
           assert_equal @db_datetime_003, existing_003.datetime_before_type_cast if existing_003.datetime_before_type_cast.is_a?(String)
           assert_equal 3000, existing_003.datetime.usec, 'A 003 millisecond in SQL Server is 3000 microseconds'
         end
-
+  
         should 'find 123 millisecond in the DB with before and after casting' do
           existing_123 = SqlServerChronic.find_by_datetime!(@db_datetime_123)
           assert_equal @db_datetime_123, existing_123.datetime_before_type_cast if existing_123.datetime_before_type_cast.is_a?(String)
           assert_equal 123000, existing_123.datetime.usec, 'A 123 millisecond in SQL Server is 123000 microseconds'
         end
-
+  
       end
 
       context 'saving new datetime objects' do
-
+  
         should 'truncate 123456 usec to just 123 in the DB cast back to 123000' do
           @time.stubs(:usec).returns(123456)
           saved = SqlServerChronic.create!(:datetime => @time).reload
@@ -350,7 +379,7 @@ def setup
       end
 
     end unless sqlserver_azure?
-
+  
     context "altering isolation levels" do
 
       should "barf if the requested isolation level is not valid" do
@@ -458,7 +487,7 @@ def setup
   context 'For views' do
 
     context 'using @connection.views' do
-
+  
       should 'return an array' do
         assert_instance_of Array, @connection.views
       end
@@ -559,7 +588,7 @@ def setup
     end
 
     context 'doing identity inserts' do
-
+  
       setup do
         @view_insert_sql = "INSERT INTO [customers_view] ([id],[name],[balance]) VALUES (420,'Microsoft',0)"
       end
@@ -572,11 +601,11 @@ def setup
         assert_nothing_raised { @connection.execute(@view_insert_sql) }
         assert CustomersView.find(420)
       end
-
+  
     end
 
     context 'that have more than 4000 chars for their defintion' do
-
+  
       should 'cope with null returned for the defintion' do
         assert_nothing_raised() { StringDefaultsBigView.columns }
       end
@@ -585,7 +614,7 @@ def setup
         assert_equal 'null', StringDefaultsBigView.new.pretend_null, 
           StringDefaultsBigView.columns_hash['pretend_null'].inspect
       end
-
+  
     end
 
   end

test/cases/sqlserver_helper.rb

@@ -26,6 +26,8 @@
 
 # Defining our classes in one place as well as soem core tests that need coercing date/time types.
 
+class UpperTestDefault < ActiveRecord::Base ; self.table_name = 'UPPER_TESTS' ; end
+class UpperTestLowered < ActiveRecord::Base ; self.table_name = 'upper_tests' ; end
 class TableWithRealColumn < ActiveRecord::Base; end
 class FkTestHasFk < ActiveRecord::Base ; end
 class FkTestHasPk < ActiveRecord::Base ; end

test/schema/sqlserver_specific_schema.rb

@@ -1,5 +1,10 @@
 ActiveRecord::Schema.define do
 
+  create_table :UPPER_TESTS, :force => true do |t|
+    t.column :COLUMN1, :string
+    t.column :COLUMN2, :integer
+  end
+  
   create_table :table_with_real_columns, :force => true do |t|
     t.column :real_number, :real
   end