Contents

require "csql/version"
require 'open3'
require 'csv'
require 'sql-parser'

module CSQL
  class SQL
    def initialize(filepath)
      @parser = SQLParser::Parser.new
      @filepath = filepath
    end

    def execute query
      begin
        modified_query = query.gsub(/csv/, @filepath)
        result,err,process = Open3.capture3("q -H -d \',\' \'#{modified_query}\'")
        if err != ""
          raise CSQLException.new(err)
        end
      end
      ast = @parser.scan_str(query)
      column = ast.query_expression.list.to_sql
      columns = nil
      if column == "*"
        columns = CSV.table(@filepath).headers.map(&:to_s)
      else
        columns = column.chomp.split(',').map{|c|c.gsub('`','').split(/as|AS/).last.strip}
      end
      return result.chomp.split("\n").map{|r|
        data = r.split(",")
        hash = Hash.new
        data.size.times do |i|
          hash[columns[i]] = data[i]
        end
        hash
      }
    end
  end

  class CSQLException < Exception
  end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
csql-0.1.2	lib/csql.rb