SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (90, 47, 138, 85, 84, 139)

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_products",
      "access_type": "range",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["product_id"],
      "rows": 6,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (90,47,138,85,84,139)"
    }
  }
}

Result

product_id product_code product_type status company_id list_price amount weight length width height shipping_freight low_avail_limit timestamp updated_timestamp usergroup_ids is_edp edp_shipping unlimited_download tracking free_shipping zero_price_action is_pbp is_op is_oper is_returnable return_period avail_since out_of_stock_actions localization min_qty max_qty qty_step list_qty_count tax_ids age_verification age_limit options_type exceptions_type details_layout shipping_params parent_product_id addon_ship_start_date
47 J0047KCW09 P A 1 0.00 10 0.000 0 0 0 0.00 0 1328558400 1328684302 0 N N N N Y N N Y 10 0 N N 0 default a:5:{s:16:"min_items_in_box";i:0;s:16:"max_items_in_box";i:0;s:10:"box_length";i:0;s:9:"box_width";i:0;s:10:"box_height";i:0;} 0 0
84 P0084TFPRL P A 1 0.00 10 0.000 0 0 0 0.00 0 1328644800 1328685169 0 N N N N Y N N Y 10 0 N N 0 default a:5:{s:16:"min_items_in_box";i:0;s:16:"max_items_in_box";i:0;s:10:"box_length";i:0;s:9:"box_width";i:0;s:10:"box_height";i:0;} 0 0
85 W0085XKO7V P A 1 0.00 15 0.000 0 0 0 0.00 0 1328644800 1328685451 0 N N N N Y N N Y 10 0 N N 0 default a:5:{s:16:"min_items_in_box";i:0;s:16:"max_items_in_box";i:0;s:10:"box_length";i:0;s:9:"box_width";i:0;s:10:"box_height";i:0;} 0 0
90 Y0090CLU50 P A 1 0.00 10 0.000 0 0 0 0.00 0 1328644800 1328686050 0 N N N N Y N N Y 10 0 N N 0 default a:5:{s:16:"min_items_in_box";i:0;s:16:"max_items_in_box";i:0;s:10:"box_length";i:0;s:9:"box_width";i:0;s:10:"box_height";i:0;} 0 0
138 G0138IU32J P A 1 0.00 0 0.000 0 0 0 0.00 0 1328644800 1328694760 0 N N N N Y N N Y 10 0 B N 0 default a:5:{s:16:"min_items_in_box";i:0;s:16:"max_items_in_box";i:0;s:10:"box_length";i:0;s:9:"box_width";i:0;s:10:"box_height";i:0;} 0 0
139 Z0139588PS P A 1 0.00 0 0.000 0 0 0 0.00 0 1328644800 1328694906 0 N N N N Y N N Y 10 0 S N 0 default a:5:{s:16:"min_items_in_box";i:0;s:16:"max_items_in_box";i:0;s:10:"box_length";i:0;s:9:"box_width";i:0;s:10:"box_height";i:0;} 0 0