def where *conditions, &block
    raise ArgumentError.new("Wrong number of arguments") if conditions.empty?

    obj = self.dup
    obj.instance_variable_set :@query_where, @query_where + conditions
    ret obj, &block
  end
def where *conditions, &block
    raise ArgumentError.new("Wrong number of arguments") if conditions.empty?

    obj = self.dup
    obj.instance_variable_set :@query_where, @query_where + conditions
    ret obj, &block
  end
Returns a new TableWrapper object which can be used to execute a select
 statement for the table with the specified filter conditions.
 If a block is given, executes the select statement and yields each row to the block.
 @param [List of Hash/String] conditions Filter conditions
 @return [JDBCHelper::TableWrapper]
 @since 0.4.0