@@ -1,5 +1,7 @@ === HEAD +* Make the JDBC adapter accept a :convert_types option to turn off Java type conversion and double performance (jeremyevans) + * Slight increase in ConnectionPool performance (jeremyevans) * SQL::WindowFunction can now be aliased/casted etc. just like SQL::Function (jeremyevans) CHANGELOG @@ -203,6 +203,13 @@ Example connections strings: jdbc:mysql://localhost/test?user=root&password=root jdbc:h2:mem: +The following additional options are supported: + +* :convert_types - If set to false, does not attempt to convert some Java types to ruby types. + Setting to false roughly doubles performance when selecting large numbers of rows. + Note that you can't provide this option inside the connection string (as that is passed + directly to JDBC), you have to pass it as a separate option. + === mysql The MySQL adapter does not support the pure-ruby MySQL adapter that ships with doc/opening_databases.rdoc @@ -88,12 +88,18 @@ module Sequel # The type of database we are connecting to attr_reader :database_type + # Whether to convert some Java types to ruby types when retrieving rows. + # True by default, can be set to false to roughly double performance when + # fetching rows. + attr_accessor :convert_types + # Call the DATABASE_SETUP proc directly after initialization, # so the object always uses sub adapter specific code. Also, # raise an error immediately if the connection doesn't have a # uri, since JDBC requires one. def initialize(opts) @opts = opts + @convert_types = opts.include?(:convert_types) ? typecast_value_boolean(opts[:convert_types]) : true raise(Error, "No connection string specified") unless uri if match = /\Ajdbc:([^:]+)/.match(uri) and prok = DATABASE_SETUP[match[1].to_sym] prok.call(self) @@ -418,6 +424,17 @@ module Sequel end end + # Whether to convert some Java types to ruby types when retrieving rows. + # Uses the database's setting by default, can be set to false to roughly + # double performance when fetching rows. + attr_accessor :convert_types + + # Use the convert_types default setting from the database + def initialize(db, opts={}) + @convert_types = db.convert_types + super + end + # Correctly return rows from the database and return them as hashes. def fetch_rows(sql, &block) execute(sql){|result| process_result_set(result, &block)} @@ -470,10 +487,16 @@ module Sequel i = 0 meta.getColumnCount.times{cols << [output_identifier(meta.getColumnLabel(i+=1)), i]} @columns = cols.map{|c| c.at(0)} + row = {} + blk = if @convert_types + lambda{|n, i| row[n] = convert_type(result.getObject(i))} + else + lambda{|n, i| row[n] = result.getObject(i)} + end # get rows while result.next row = {} - cols.each{|n, i| row[n] = convert_type(result.getObject(i))} + cols.each(&blk) yield row end end lib/sequel/adapters/jdbc.rb 178c1e4b3acd8be2c823d6a0c50d5dc14a1ecadb Jeremy Evans code@jeremyevans.net http://github.com/jeremyevans/sequel/commit/af2ba1b780afd7013dfd1321dfd708f9816eeb50 af2ba1b780afd7013dfd1321dfd708f9816eeb50 2009-07-08T11:23:33-07:00 2009-07-08T11:23:33-07:00 Make the JDBC adapter accept a :convert_types option to turn off Java type conversion and double performance This gives the user the choice to turn off conversion from Java types to ruby types, in order to roughly double the performance when fetching rows. This can be set at both the database and dataset level: DB = Sequel.jdbc('jdbc:postgresql://host/database', :convert_types=>false) DB.convert_types = true ds = DB[:table] ds.convert_types = true If you turn off Java type conversion, Date, DateTime, Time, and BigDecimal fields will probably be returned as Java types, which have a different API than ruby types. I recommend only turning it off if there is a bottleneck in your application, and then only for the dataset that is the bottleneck. Since Sequel allows you to modify the setting at the dataset level, that's fairly easy to do. Note that the setting is not a database option like :from, its a setting like quote_identifiers, and modifies the dataset directly instead of returning a modified copy, so use with care. e69ecdf650c7029710603e556e5c63051e320743 Jeremy Evans code@jeremyevans.net