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SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.meta_keywords, 
  cscart_product_descriptions.meta_description, 
  cscart_product_descriptions.search_words, 
  cscart_product_descriptions.promo_text 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (306, 316, 307, 322, 505) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": ["PRIMARY", "product_id"],
      "key": "PRIMARY",
      "key_length": "9",
      "used_key_parts": ["product_id", "lang_code"],
      "rows": 5,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (306,316,307,322,505) and cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id	meta_keywords	meta_description
306	sony, a7II, a7RII, ILCE-7M2, Camera, Tripod, Head, Quick, Shoe, Clamp, Plate, Arca-Swiss, rrs, kirk, foba	For Sony a7II a7RII. Markins PS-A72 is an anti-twist style camera plate for Sony A7II camera. It can be converted to an L-Plate(L-bracket) with optional sub plate LS-A72.
307	Camera, Tripod, Head, Quick, Shoe, Clamp, Plate, Arca-Swiss, rrs, kirk, foba, universal	Markins PU-40 is a universal style camera plate for medium sized SLR cameras. It has a rubber bumpons for anti-twisting.
316	Camera, Tripod, Head, Quick, Shoe, Clamp, Plate, Bracket, Arca-Swiss, rrs, kirk, foba	For Sony α7II α7RII. Optional LS-A72 for PS-A72 to convert it to L-Plate（L-Bracket）
322	Camera, Tripod, Head, Quick, Shoe, Clamp, Plate, Foot, Arca-Swiss, rrs, kirk, foba	Markins PC-14 is an Arca-Swiss compatible style dovetail plate for Canon EF 100-400mm f/4.5-5.6L IS II USM lens.
505