Goodbye MongoDB, Hello PostgreSQL(developer.olery.com)

  s = Select.new
  s.add "WHERE title LIKE #{title}" if title
  s.add "WHERE price <= #{price_range}" if price_range
  s.add "LIMIT #{limit}" if limit
  s.add "OFFSET #{offset}" if offset
  s.add "id, blah, boo FROM products"
  s.execute

    sql = 'SELECT * FROM products'
    args = []

    if title:
        sql += ' WHERE title LIKE %?%'
        args.append(title)

    if upc:
        if args:
            sql += ' AND'
        else:
            sql += ' WHERE'
        sql += ' upc LIKE %?%' 
        args.append(upc)

    if price_min:
        if args:
            sql += ' AND'
        else:
            sql += ' WHERE'
        sql += ' price >= ?'
        args.append(price_min)

    if price_max:
        if args:
            sql += ' AND'
        else:
            sql += ' WHERE'
        sql += ' price <= ?'
        args.append(price_max)

    if order_by_name:
        sql += ' ORDER BY name'
    elif order_by_price_low:
        sql += ' ORDER BY price'
    elif order_by_price_high:
        sql += ' ORDER BY price DESC'


    conn.query(sql, args)

    query = sprintf("select count(*) from data where %s = ?", column)
    results = sql.execute(query, filter_value);

    WHERE (_title    IS NULL OR title LIKE _title)
    AND   (_minPrice IS NULL OR price > _minPrice)
    AND   (_maxPrice IS NULL OR price < _maxPrice)

    WHERE (:1 IS NULL OR :1 = item_id)
      AND item_num BETWEEN NVL(:2,0) AND NVL(:2,9999999999)
      AND item_date BETWEEN NVL(:3,'01-jan-1900') AND NVL(:3,'31-dec-4712')
      AND item_name LIKE NVL(:4,'%')
    ORDER BY
      CASE :5 WHEN 'NUM' THEN item_num WHEN 'DATE' THEN item_date ELSE item_name END,
      CASE :6 WHEN 'NUM' THEN item_num WHEN 'DATE' THEN item_date ELSE item_name END

    .FilterByEvensOnly()
    .FilterByMinimum()
    .FilterByMaximum()