Add support for FrontBase (http://www.frontbase.com/) with a new adapter thanks to the hard work of one Mike Laster. Closes #4093. [mlaster@metavillage.com]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4291 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

1 files changed, 837 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/frontbase_adapter.rb b/activerecord/lib/active_record/connection_adapters/frontbase_adapter.rb
new file mode 100644
index 0000000000..6fa2ca3ffc
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/frontbase_adapter.rb
@@ -0,0 +1,837 @@
+# Requires FrontBase Ruby bindings from: 
+# svn://rubyforge.org/var/svn/frontbase-rails/trunk/ruby-frontbase
+
+require 'active_record/connection_adapters/abstract_adapter'
+require 'frontbase'
+
+FB_TRACE = false
+
+module ActiveRecord
+
+  class Base
+
+    class << self
+      # FrontBase only supports one unnamed sequence per table
+      def set_sequence_name( value=nil, &block )
+      end
+      
+      # Establishes a connection to the database that's used by all Active Record objects.
+      def frontbase_connection(config) # :nodoc:
+        config = config.symbolize_keys
+        database     = config[:database]
+        port         = config[:port]
+        host         = config[:host]
+        username     = config[:username]
+        password     = config[:password]
+        dbpassword   = config[:dbpassword]
+        session_name = config[:session_name]
+
+        dbpassword = '' if dbpassword.nil?
+        
+        # Turn off colorization since it makes tail/less output difficult
+        self.colorize_logging = false
+        
+        
+        connection = FBSQL_Connect.connect(host, port, database, username, password, dbpassword, session_name)
+        ConnectionAdapters::FrontBaseAdapter.new(connection, logger, [host, port, database, username, password, dbpassword, session_name], config)
+      end            
+    end
+  end
+  
+  module ConnectionAdapters
+    
+    # From EOF Documentation....
+    # buffer should have space for EOUniqueBinaryKeyLength (12) bytes.
+    # Assigns a world-wide unique ID made up of:
+    # < Sequence [2], ProcessID [2] , Time [4], IP Addr [4] >
+    
+    class TwelveByteKey < String #:nodoc
+      @@mutex = Mutex.new
+      @@sequence_number = rand(65536)
+      @@key_cached_pid_component = nil
+      @@key_cached_ip_component = nil
+
+      def initialize(string = nil)
+        # Generate a unique key
+        if string.nil?
+          new_key = replace('_' * 12)
+
+          new_key[0..1]  = self.class.key_sequence_component        
+          new_key[2..3]  = self.class.key_pid_component
+          new_key[4..7]  = self.class.key_time_component
+          new_key[8..11] = self.class.key_ip_component
+          new_key
+        else
+          if string.size == 24
+            string.gsub!(/[[:xdigit:]]{2}/) { |x| x.hex.chr }
+          end
+          raise "string is not 12 bytes long" unless string.size == 12
+          super(string)
+        end
+      end
+            
+      def inspect
+        unpack("H*").first.upcase
+      end
+    
+      alias_method :to_s, :inspect
+      
+      private
+            
+        class << self
+          def key_sequence_component
+            seq = nil
+            @@mutex.synchronize do
+              seq = @@sequence_number
+              @@sequence_number = (@@sequence_number + 1) % 65536
+            end
+            
+            sequence_component = "__"
+            sequence_component[0] = seq >> 8
+            sequence_component[1] = seq
+            sequence_component
+          end
+          
+          def key_pid_component
+            if @@key_cached_pid_component.nil?
+              @@mutex.synchronize do
+                pid = $$
+                pid_component = "__"
+                pid_component[0] = pid >> 8
+                pid_component[1] = pid
+                @@key_cached_pid_component = pid_component
+              end
+            end
+            @@key_cached_pid_component
+          end
+          
+          def key_time_component
+            time = Time.new.to_i
+            time_component = "____"
+            time_component[0] = (time & 0xFF000000) >> 24
+            time_component[1] = (time & 0x00FF0000) >> 16
+            time_component[2] = (time & 0x0000FF00) >> 8
+            time_component[3] = (time & 0x000000FF)
+            time_component
+          end
+          
+          def key_ip_component
+            if @@key_cached_ip_component.nil?
+              @@mutex.synchronize do
+                old_lookup_flag  = BasicSocket.do_not_reverse_lookup
+                BasicSocket.do_not_reverse_lookup = true
+                udpsocket = UDPSocket.new
+                udpsocket.connect("17.112.152.32",1)
+                ip_string = udpsocket.addr[3]
+                BasicSocket.do_not_reverse_lookup = old_lookup_flag
+                packed = Socket.pack_sockaddr_in(0,ip_string)
+                addr_subset = packed[4..7]
+                ip = addr_subset[0] << 24 | addr_subset[1] << 16 | addr_subset[2] << 8 | addr_subset[3]
+                ip_component = "____"
+                ip_component[0] = (ip & 0xFF000000) >> 24
+                ip_component[1] = (ip & 0x00FF0000) >> 16
+                ip_component[2] = (ip & 0x0000FF00) >> 8
+                ip_component[3] = (ip & 0x000000FF)
+                @@key_cached_ip_component = ip_component
+              end
+            end
+            @@key_cached_ip_component
+          end
+        end
+    end
+    
+    class FrontBaseColumn < Column #:nodoc:
+      attr_reader :fb_autogen
+      
+      def initialize(base, name, type, typename, limit, precision, scale, default, nullable)
+        
+        @base       = base
+        @name       = name
+        @type       = simplified_type(type,typename,limit)
+        @limit      = limit
+        @precision  = precision
+        @scale      = scale
+        @default    = default
+        @null       = nullable == "YES"
+        @text       = [:string, :text].include? @type
+        @number     = [:float, :integer].include? @type
+        @fb_autogen = false
+
+        if @default
+          @default.gsub!(/^'(.*)'$/,'\1') if @text
+          @fb_autogen =  @default.include?("SELECT UNIQUE FROM")
+          case @type
+          when :boolean 
+            @default = @default == "TRUE"
+          when :binary
+            if @default != "X''"
+              buffer = ""
+              @default.scan(/../) { |h| buffer << h.hex.chr }
+              @default = buffer
+            else
+              @default = ""
+            end
+          else
+            @default = type_cast(@default)
+          end
+        end
+      end
+      
+      # Casts value (which is a String) to an appropriate instance.
+      def type_cast(value)
+        if type == :twelvebytekey
+          ActiveRecord::ConnectionAdapters::TwelveByteKey.new(value)
+        else
+          super(value)
+        end
+      end
+
+      def type_cast_code(var_name)
+        if type == :twelvebytekey
+          "ActiveRecord::ConnectionAdapters::TwelveByteKey.new(#{var_name})"
+        else
+          super(var_name)
+        end
+      end
+
+      private
+        def simplified_type(field_type, type_name,limit)
+          ret_type = :string
+          puts "typecode: [#{field_type}] [#{type_name}]"  if FB_TRACE
+
+          # 12 byte primary keys are a special case that Apple's EOF
+          # used heavily.  Optimize for this case
+          if field_type == 11 && limit == 96
+           ret_type = :twelvebytekey            # BIT(96)
+          else
+           ret_type = case field_type
+             when 1  then :boolean   # BOOLEAN
+             when 2  then :integer   # INTEGER
+             when 4  then :float     # FLOAT
+             when 10 then :string    # CHARACTER VARYING
+             when 11 then :bitfield  # BIT
+             when 13 then :date      # DATE
+             when 14 then :time      # TIME
+             when 16 then :timestamp # TIMESTAMP
+             when 20 then :text      # CLOB
+             when 21 then :binary    # BLOB
+             when 22 then :integer   # TINYINT
+             else
+               puts "ERROR: Unknown typecode: [#{field_type}] [#{type_name}]"
+           end
+          end
+          puts "ret_type: #{ret_type.inspect}" if FB_TRACE
+          ret_type
+        end
+    end
+
+    class FrontBaseAdapter < AbstractAdapter
+            
+      def initialize(connection, logger, connection_options, config)
+        super(connection, logger)
+        @connection_options, @config = connection_options, config
+        @transaction_mode = :pessimistic
+        
+        # threaded_connections_test.rb will fail unless we set the session
+        # to optimistic locking mode
+#         set_pessimistic_transactions
+#         execute "SET TRANSACTION ISOLATION LEVEL REPEATABLE READ, READ WRITE, LOCKING OPTIMISTIC"
+      end
+
+      # Returns the human-readable name of the adapter.  Use mixed case - one
+      # can always use downcase if needed.
+      def adapter_name #:nodoc:
+        'FrontBase'
+      end
+
+      # Does this adapter support migrations?  Backend specific, as the
+      # abstract adapter always returns +false+.
+      def supports_migrations? #:nodoc:
+        true
+      end
+
+      def native_database_types #:nodoc
+        {
+          :primary_key    => "INTEGER DEFAULT UNIQUE PRIMARY KEY",
+          :string         => { :name => "VARCHAR", :limit => 255 },
+          :text           => { :name => "CLOB" },
+          :integer        => { :name => "INTEGER" },
+          :float          => { :name => "FLOAT" },
+          :datetime       => { :name => "TIMESTAMP" },
+          :timestamp      => { :name => "TIMESTAMP" },
+          :time           => { :name => "TIME" },
+          :date           => { :name => "DATE" },
+          :binary         => { :name => "BLOB" },
+          :boolean        => { :name => "BOOLEAN" },
+          :twelvebytekey  => { :name => "BYTE", :limit => 12}
+        }
+      end
+
+
+      # QUOTING ==================================================
+
+      # Quotes the column value to help prevent
+      # {SQL injection attacks}[http://en.wikipedia.org/wiki/SQL_injection].
+      def quote(value, column = nil)
+        retvalue = "<INVALID>"
+   
+        puts "quote(#{value.inspect}(#{value.class}),#{column.type.inspect})" if FB_TRACE
+        # If a column was passed in, use column type information
+        unless value.nil?
+          if column
+            retvalue = case column.type
+              when :string
+                if value.kind_of?(String)
+                  "'#{quote_string(value.to_s)}'" # ' (for ruby-mode)
+                else
+                  "'#{quote_string(value.to_yaml)}'"
+                end
+              when :integer
+                if value.kind_of?(TrueClass)
+                  '1'
+                elsif value.kind_of?(FalseClass)
+                  '0'
+                else
+                   value.to_i.to_s
+                end
+              when :float
+                value.to_f.to_s
+              when :datetime, :timestamp
+                "TIMESTAMP '#{value.strftime("%Y-%m-%d %H:%M:%S")}'"
+              when :time
+                "TIME '#{value.strftime("%H:%M:%S")}'"
+              when :date
+                "DATE '#{value.strftime("%Y-%m-%d")}'"
+              when :twelvebytekey
+                value = value.to_s.unpack("H*").first unless value.kind_of?(TwelveByteKey)
+                "X'#{value.to_s}'"
+              when :boolean
+                value = quoted_true if value.kind_of?(TrueClass)
+                value = quoted_false if value.kind_of?(FalseClass)
+                value
+              when :binary
+                blob_handle = @connection.create_blob(value.to_s)
+                puts "SQL -> Insert #{value.to_s.length} byte blob as #{retvalue}" if FB_TRACE
+                blob_handle.handle
+              when :text
+                if value.kind_of?(String)
+                  clobdata = value.to_s # ' (for ruby-mode)
+                else
+                  clobdata = value.to_yaml
+                end
+                clob_handle = @connection.create_clob(clobdata)
+                puts "SQL -> Insert #{value.to_s.length} byte clob as #{retvalue}" if FB_TRACE
+                clob_handle.handle
+              else
+                raise "*** UNKNOWN TYPE: #{column.type.inspect}"
+            end # case
+          # Since we don't have column type info, make a best guess based
+          # on the Ruby class of the value
+          else
+            retvalue = case value
+              when ActiveRecord::ConnectionAdapters::TwelveByteKey
+                s = value.unpack("H*").first
+                "X'#{s}'"
+              when String
+                if column && column.type == :binary
+                  s = value.unpack("H*").first
+                  "X'#{s}'"
+                elsif column && [:integer, :float].include?(column.type) 
+                  value.to_s
+                else
+                  "'#{quote_string(value)}'" # ' (for ruby-mode)
+                end
+              when NilClass
+                "NULL"
+              when TrueClass
+                (column && column.type == :integer ? '1' : quoted_true)
+              when FalseClass
+                (column && column.type == :integer ? '0' : quoted_false)
+              when Float, Fixnum, Bignum
+                value.to_s
+              when Time, Date, DateTime
+                if column
+                  case column.type
+                    when :date
+                      "DATE '#{value.strftime("%Y-%m-%d")}'"
+                    when :time
+                      "TIME '#{value.strftime("%H:%M:%S")}'"
+                    when :timestamp
+                      "TIMESTAMP '#{value.strftime("%Y-%m-%d %H:%M:%S")}'"
+                  else
+                    raise NotImplementedError, "Unknown column type!"
+                  end # case
+                else # Column wasn't passed in, so try to guess the right type
+                  if value.kind_of? Date
+                    "DATE '#{value.strftime("%Y-%m-%d")}'"
+                  else
+                    if [:hour, :min, :sec].all? {|part| value.send(:part).zero? }
+                      "TIME '#{value.strftime("%H:%M:%S")}'"
+                    else
+                      "TIMESTAMP '#{quoted_date(value)}'"
+                    end
+                  end 
+                end #if column
+              else 
+                "'#{quote_string(value.to_yaml)}'"
+            end #case
+          end
+        else
+          retvalue = "NULL"
+        end
+         
+        retvalue
+      end # def
+
+      # Quotes a string, escaping any ' (single quote) characters.
+      def quote_string(s)
+        s.gsub(/'/, "''") # ' (for ruby-mode)
+      end
+
+      def quote_column_name(name) #:nodoc:
+        %( "#{name}" )
+      end
+
+      def quoted_true
+        "true"
+      end
+      
+      def quoted_false
+        "false"
+      end
+
+
+      # CONNECTION MANAGEMENT ====================================
+
+      def active?
+        true if @connection.status == 1
+      rescue => e
+        false
+      end
+
+      def reconnect!
+        @connection.close rescue nil
+        @connection = FBSQL_Connect.connect(*@connection_options.first(7))
+      end
+
+      # Close this connection
+      def disconnect!
+        @connection.close rescue nil
+        @active = false
+      end
+
+      # DATABASE STATEMENTS ======================================
+
+      # Returns an array of record hashes with the column names as keys and
+      # column values as values.
+      def select_all(sql, name = nil) #:nodoc:
+        fbsql        = cleanup_fb_sql(sql)
+        return_value = []
+        fbresult     = execute(sql, name)
+        puts "select_all SQL -> #{fbsql}" if FB_TRACE
+        columns = fbresult.columns
+
+        fbresult.each do |row|
+          puts "SQL <- #{row.inspect}"  if FB_TRACE
+          hashed_row = {}    
+          colnum     = 0
+          row.each do |col|
+            hashed_row[columns[colnum]] = col
+            if col.kind_of?(FBSQL_LOB)
+              hashed_row[columns[colnum]] = col.read
+            end
+            colnum += 1
+          end
+          puts "raw row: #{hashed_row.inspect}" if FB_TRACE
+          return_value << hashed_row
+        end
+        return_value
+      end
+
+      def select_one(sql, name = nil) #:nodoc:
+        fbsql        = cleanup_fb_sql(sql)
+        return_value = []
+        fbresult     = execute(fbsql, name)
+        puts "SQL -> #{fbsql}"  if FB_TRACE
+        columns = fbresult.columns
+        
+        fbresult.each do |row|
+          puts "SQL <- #{row.inspect}"  if FB_TRACE
+          hashed_row = {}    
+          colnum     = 0
+          row.each do |col|
+            hashed_row[columns[colnum]] = col
+            if col.kind_of?(FBSQL_LOB)
+              hashed_row[columns[colnum]] = col.read
+            end
+            colnum += 1
+          end
+          return_value << hashed_row
+          break
+        end
+        fbresult.clear
+        return_value.first
+      end
+
+      def query(sql, name = nil) #:nodoc:
+        fbsql = cleanup_fb_sql(sql)
+        puts "SQL(query) -> #{fbsql}"  if FB_TRACE
+        log(fbsql, name) { @connection.query(fbsql) }
+      rescue => e
+        puts "FB Exception: #{e.inspect}" if FB_TRACE
+        raise e
+      end
+
+      def execute(sql, name = nil) #:nodoc:
+        fbsql = cleanup_fb_sql(sql)
+        puts "SQL(execute) -> #{fbsql}"  if FB_TRACE
+        log(fbsql, name) { @connection.query(fbsql) }
+      rescue ActiveRecord::StatementInvalid => e
+        if e.message.scan(/Table name - \w* - exists/).empty?
+          puts "FB Exception: #{e.inspect}" if FB_TRACE
+          raise e
+        end
+      end
+      
+      # Returns the last auto-generated ID from the affected table.
+      def insert(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) #:nodoc:
+        puts "SQL -> #{sql.inspect}"  if FB_TRACE
+        execute(sql, name)
+        id_value || pk
+      end
+
+      # Executes the update statement and returns the number of rows affected.
+      def update(sql, name = nil) #:nodoc:
+        puts "SQL -> #{sql.inspect}"  if FB_TRACE
+        execute(sql, name).num_rows
+      end
+
+      alias_method :delete, :update #:nodoc:
+
+      def set_pessimistic_transactions
+        if @transaction_mode == :optimistic
+          execute "SET TRANSACTION ISOLATION LEVEL SERIALIZABLE, LOCKING PESSIMISTIC, READ WRITE"
+          @transaction_mode = :pessimistic
+        end
+      end
+
+      def set_optimistic_transactions
+        if @transaction_mode == :pessimistic
+          execute "SET TRANSACTION ISOLATION LEVEL REPEATABLE READ, READ WRITE, LOCKING OPTIMISTIC"
+          @transaction_mode = :optimistic
+        end
+      end
+
+      def begin_db_transaction #:nodoc:
+        execute "SET COMMIT FALSE" rescue nil
+      end
+
+      def commit_db_transaction #:nodoc:
+        execute "COMMIT"
+      ensure
+        execute "SET COMMIT TRUE"
+      end
+
+      def rollback_db_transaction #:nodoc:
+        execute "ROLLBACK"
+      ensure
+        execute "SET COMMIT TRUE"
+      end
+
+      def add_limit_offset!(sql, options) #:nodoc
+        if limit = options[:limit]
+          offset = options[:offset] || 0
+        
+# Here is the full syntax FrontBase supports:
+# (from gclem@frontbase.com)
+# 
+#       TOP <limit - unsigned integer>
+#       TOP ( <offset expr>, <limit expr>)
+        
+          # "TOP 0" is not allowed, so we have
+          # to use a cheap trick.
+          if limit.zero?
+            case sql
+            when /WHERE/i
+              sql.sub!(/WHERE/i, 'WHERE 0 = 1 AND ')
+            when /ORDER\s+BY/i
+              sql.sub!(/ORDER\s+BY/i, 'WHERE 0 = 1 ORDER BY')
+            else
+              sql << 'WHERE 0 = 1'
+            end
+          else
+            if offset.zero?
+              sql.replace sql.gsub("SELECT ","SELECT TOP #{limit} ")
+            else
+              sql.replace sql.gsub("SELECT ","SELECT TOP(#{offset},#{limit}) ")
+            end
+          end
+        end
+      end
+
+      def prefetch_primary_key?(table_name = nil)
+        true
+      end
+
+      # Returns the next sequence value from a sequence generator. Not generally
+      # called directly; used by ActiveRecord to get the next primary key value
+      # when inserting a new database record (see #prefetch_primary_key?).
+      def next_sequence_value(sequence_name)
+        unique = select_value("SELECT UNIQUE FROM #{sequence_name}","Next Sequence Value")
+        # The test cases cannot handle a zero primary key
+        unique.zero? ? select_value("SELECT UNIQUE FROM #{sequence_name}","Next Sequence Value") : unique
+      end
+
+      def default_sequence_name(table, column)
+        table
+      end
+
+      # Set the sequence to the max value of the table's column.
+      def reset_sequence!(table, column, sequence = nil)
+        klasses = classes_for_table_name(table)
+        klass   = klasses.nil? ? nil : klasses.first
+        pk      = klass.primary_key unless klass.nil?
+        if pk && klass.columns_hash[pk].type == :integer
+          execute("SET UNIQUE FOR #{klass.table_name}(#{pk})")
+        end
+      end
+
+      def classes_for_table_name(table)
+        ActiveRecord::Base.send(:subclasses).select {|klass| klass.table_name == table}
+      end
+      
+      def reset_pk_sequence!(table, pk = nil, sequence = nil)
+        klasses = classes_for_table_name(table)
+        klass   = klasses.nil? ? nil : klasses.first
+        pk      = klass.primary_key unless klass.nil?
+        if pk && klass.columns_hash[pk].type == :integer
+          mpk = select_value("SELECT MAX(#{pk}) FROM #{table}")
+          execute("SET UNIQUE FOR #{klass.table_name}(#{pk})")
+        end
+      end
+
+      # SCHEMA STATEMENTS ========================================
+
+      def structure_dump #:nodoc:
+        select_all("SHOW TABLES").inject('') do |structure, table|
+          structure << select_one("SHOW CREATE TABLE #{table.to_a.first.last}")["Create Table"] << ";\n\n"
+        end
+      end
+
+      def recreate_database(name) #:nodoc:
+        drop_database(name)
+        create_database(name)
+      end
+
+      def create_database(name) #:nodoc:
+        execute "CREATE DATABASE #{name}"
+      end
+      
+      def drop_database(name) #:nodoc:
+        execute "DROP DATABASE #{name}"
+      end
+
+      def current_database
+        select_value('SELECT "CATALOG_NAME" FROM INFORMATION_SCHEMA.CATALOGS').downcase
+      end
+
+      def tables(name = nil) #:nodoc:
+        select_values(<<-SQL, nil)
+          SELECT "TABLE_NAME" 
+          FROM   INFORMATION_SCHEMA.TABLES   AS T0,
+                 INFORMATION_SCHEMA.SCHEMATA AS T1 
+          WHERE  T0.SCHEMA_PK  = T1.SCHEMA_PK 
+          AND    "SCHEMA_NAME" = CURRENT_SCHEMA
+        SQL
+      end
+
+      def indexes(table_name, name = nil)#:nodoc:
+        indexes = []
+        current_index = nil
+        sql = <<-SQL
+          SELECT   INDEX_NAME, T2.ORDINAL_POSITION, INDEX_COLUMN_COUNT, INDEX_TYPE, 
+                   "COLUMN_NAME", IS_NULLABLE 
+          FROM     INFORMATION_SCHEMA.TABLES             AS T0, 
+                   INFORMATION_SCHEMA.INDEXES            AS T1, 
+                   INFORMATION_SCHEMA.INDEX_COLUMN_USAGE AS T2, 
+                   INFORMATION_SCHEMA.COLUMNS            AS T3 
+          WHERE    T0."TABLE_NAME" = '#{table_name}' 
+            AND    INDEX_TYPE <> 0 
+            AND    T0.TABLE_PK   = T1.TABLE_PK 
+            AND    T0.TABLE_PK   = T2.TABLE_PK 
+            AND    T0.TABLE_PK   = T3.TABLE_PK 
+            AND    T1.INDEXES_PK = T2.INDEX_PK 
+            AND    T2.COLUMN_PK  = T3.COLUMN_PK 
+          ORDER BY INDEX_NAME, T2.ORDINAL_POSITION
+        SQL
+
+        columns = []
+        query(sql).each do |row|
+          index_name   = row[0]
+          ord_position = row[1]
+          ndx_colcount = row[2]
+          index_type   = row[3]
+          column_name  = row[4]
+          
+          is_unique = index_type == 1
+          
+          columns << column_name
+          if ord_position == ndx_colcount
+            indexes << IndexDefinition.new(table_name, index_name, is_unique , columns)
+            columns = []
+          end
+        end
+        indexes
+      end
+
+      def columns(table_name, name = nil)#:nodoc:
+        sql = <<-SQL
+          SELECT   "TABLE_NAME", "COLUMN_NAME", ORDINAL_POSITION, IS_NULLABLE, COLUMN_DEFAULT, 
+                   DATA_TYPE, DATA_TYPE_CODE, CHARACTER_MAXIMUM_LENGTH, NUMERIC_PRECISION, 
+                   NUMERIC_PRECISION_RADIX, NUMERIC_SCALE, DATETIME_PRECISION, DATETIME_PRECISION_LEADING 
+          FROM     INFORMATION_SCHEMA.TABLES               T0, 
+                   INFORMATION_SCHEMA.COLUMNS              T1, 
+                   INFORMATION_SCHEMA.DATA_TYPE_DESCRIPTOR T3 
+          WHERE    "TABLE_NAME" = '#{table_name}' 
+            AND    T0.TABLE_PK  = T1.TABLE_PK 
+            AND    T0.TABLE_PK  = T3.TABLE_OR_DOMAIN_PK 
+            AND    T1.COLUMN_PK = T3.COLUMN_NAME_PK 
+          ORDER BY T1.ORDINAL_POSITION
+        SQL
+
+        rawresults = query(sql,name)
+        columns = []
+        rawresults.each do |field|
+          args = [base       = field[0],
+                  name       = field[1],
+                  typecode   = field[6],
+                  typestring = field[5],
+                  limit      = field[7],
+                  precision  = field[8],
+                  scale      = field[9],
+                  default    = field[4],
+                  nullable   = field[3]]
+          columns << FrontBaseColumn.new(*args)
+         end
+        columns
+      end
+      
+      def create_table(name, options = {})
+        table_definition = TableDefinition.new(self)
+        table_definition.primary_key(options[:primary_key] || "id") unless options[:id] == false
+
+        yield table_definition
+
+        if options[:force]
+          drop_table(name) rescue nil
+        end
+
+        create_sql = "CREATE#{' TEMPORARY' if options[:temporary]} TABLE "
+        create_sql << "#{name} ("
+        create_sql << table_definition.to_sql
+        create_sql << ") #{options[:options]}"
+        begin_db_transaction
+        execute create_sql
+        commit_db_transaction
+        rescue ActiveRecord::StatementInvalid => e
+          raise e unless e.message.match(/Table name - \w* - exists/)
+      end
+      
+      def rename_table(name, new_name)
+        columns = columns(name)
+        pkcol = columns.find {|c| c.fb_autogen}
+        execute "ALTER TABLE NAME #{name} TO #{new_name}"
+        if pkcol
+          change_column_default(new_name,pkcol.name,"UNIQUE")
+          begin_db_transaction
+          mpk = select_value("SELECT MAX(#{pkcol.name}) FROM #{new_name}")
+          mpk = 0 if mpk.nil?
+          execute "SET UNIQUE=#{mpk} FOR #{new_name}"
+          commit_db_transaction
+        end
+      end  
+
+      # Drops a table from the database.
+      def drop_table(name)
+        execute "DROP TABLE #{name} RESTRICT"
+      rescue ActiveRecord::StatementInvalid => e
+        raise e unless e.message.match(/Referenced TABLE - \w* - does not exist/)
+      end
+
+      # Adds a new column to the named table.
+      # See TableDefinition#column for details of the options you can use.
+      def add_column(table_name, column_name, type, options = {})
+        add_column_sql = "ALTER TABLE #{table_name} ADD #{column_name} #{type_to_sql(type, options[:limit])}"
+        options[:type] = type
+        add_column_options!(add_column_sql, options)
+        execute(add_column_sql)
+      end
+
+      def add_column_options!(sql, options) #:nodoc:
+        default_value = quote(options[:default], options[:column])
+        if options[:default]
+          if options[:type] == :boolean
+            default_value = options[:default] == 0 ? quoted_false : quoted_true
+          end
+        end
+        sql << " DEFAULT #{default_value}" unless options[:default].nil?
+        sql << " NOT NULL" if options[:null] == false
+      end
+
+      # Removes the column from the table definition.
+      # ===== Examples
+      #  remove_column(:suppliers, :qualification)
+      def remove_column(table_name, column_name)
+        execute "ALTER TABLE #{table_name} DROP #{column_name} RESTRICT"
+      end
+
+      def remove_index(table_name, options = {}) #:nodoc:
+        if options[:unique]
+          execute "ALTER TABLE #{table_name} DROP CONSTRAINT #{quote_column_name(index_name(table_name, options))} RESTRICT"
+        else
+          execute "DROP INDEX #{quote_column_name(index_name(table_name, options))}"
+        end
+      end
+
+      def change_column_default(table_name, column_name, default) #:nodoc:
+        execute "ALTER TABLE #{table_name} ALTER COLUMN #{column_name} SET DEFAULT #{default}" if default != "NULL"
+      end
+
+      def change_column(table_name, column_name, type, options = {}) #:nodoc:
+        change_column_sql = %( ALTER COLUMN "#{table_name}"."#{column_name}" TO #{type_to_sql(type, options[:limit])} )
+        execute(change_column_sql)
+        change_column_sql = %( ALTER TABLE "#{table_name}" ALTER COLUMN "#{column_name}" )
+
+        default_value = quote(options[:default], options[:column])
+        if options[:default]
+          if type == :boolean
+            default_value = options[:default] == 0 ? quoted_false : quoted_true
+          end
+        end
+
+        if default_value != "NULL"
+          change_column_sql << " SET DEFAULT #{default_value}"
+          execute(change_column_sql)
+        end
+        
+#         change_column_sql = "ALTER TABLE #{table_name} CHANGE #{column_name} #{column_name} #{type_to_sql(type, options[:limit])}"
+#         add_column_options!(change_column_sql, options)
+#         execute(change_column_sql)
+      end
+
+      def rename_column(table_name, column_name, new_column_name) #:nodoc:
+        execute %( ALTER COLUMN NAME "#{table_name}"."#{column_name}" TO "#{new_column_name}" )
+      end
+            
+      private
+      
+        # Clean up sql to make it something FrontBase can digest
+        def cleanup_fb_sql(sql) #:nodoc:
+          # Turn non-standard != into standard <>
+          cleansql = sql.gsub("!=", "<>") 
+          # Strip blank lines and comments
+          cleansql.split("\n").reject { |line| line.match(/^(?:\s*|--.*)$/) } * "\n"
+        end
+    end
+  end
+end