SELECT 
  meta_description, 
  meta_keywords 
FROM 
  cscart_category_descriptions 
WHERE 
  category_id = 0 
  AND lang_code = 'ru'

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}