Contents

module AdapterExtensions::AbstractAdapter

  # Truncate the specified table - allow to pass an optional string
  # to let the called add extra parameters like RESET IDENTITY for pg
  def truncate(table_name, options=nil)
    statement = [
      'TRUNCATE TABLE',
      table_name,
      options
    ].compact.join(' ')
    execute(statement)
  end

  # Bulk loading interface. Load the data from the specified file into the
  # given table. Note that options will be adapter-dependent.
  def bulk_load(file, table_name, options={})
    raise ArgumentError, "#{file} does not exist" unless File.exist?(file)
    raise ArgumentError, "#{table_name} does not exist" unless tables.include?(table_name)
    do_bulk_load(file, table_name, options)
  end
  
  # SQL select into statement constructs a new table from the results
  # of a select. It is used to select data from a table and create a new
  # table with its result set at the same time.  Note that this method
  # name does not necessarily match the implementation.  E.g. MySQL's
  # version of this is 'CREATE TABLE ... AS SELECT ...'
  def support_select_into_table?
    false
  end
  
  # Add a chunk of SQL to the given query that will create a new table and
  # execute the select into that table.
  def add_select_into_table(new_table_name, sql_query)
    raise NotImplementedError, "add_select_into_table is an abstract method"
  end
  
protected
  
  # for subclasses to implement
  def do_bulk_load(file, table_name, options={})
    raise NotImplementedError, "do_bulk_load is an abstract method"
  end

end

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
adapter_extensions-1.0.0	lib/adapter_extensions/adapters/abstract_adapter.rb
adapter_extensions-1.0.0.rc1	lib/adapter_extensions/adapters/abstract_adapter.rb