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SELECT 
  * 
FROM 
  cscart_product_feature_variants 
  LEFT JOIN cscart_product_feature_variant_descriptions ON cscart_product_feature_variant_descriptions.variant_id = cscart_product_feature_variants.variant_id 
  AND cscart_product_feature_variant_descriptions.lang_code = 'es' 
WHERE 
  cscart_product_feature_variants.variant_id = 117

Query time 0.00093

JSON explain

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    "nested_loop": [
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          "key": "PRIMARY",
          "used_key_parts": [
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          "used_columns": [
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            "feature_id",
            "url",
            "color",
            "position"
          ]
        }
      },
      {
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    ]
  }
}

Result

variant_id	feature_id	url	color	position	variant	description	page_title	meta_keywords	meta_description	lang_code
117	18			0	Nikon	<p><p><b>Nikon Corporation</b>, also known as just <b>Nikon</b>, is a Japanese multinational corporation headquartered in Tokyo, Japan, specializing in optics and imaging products.</p> <p>Its products include cameras, camera lenses, binoculars, microscopes, ophthalmic lenses, measurement instruments, and the steppers used in the photolithography steps of semiconductor fabrication, of which it is the world's second largest manufacturer. The companies held by Nikon form the Nikon Group. Among its products are Nikkor imaging lenses (for F-mount cameras, large format photography, photographic enlargers, and other applications), the Nikon F-series of 135 film SLR cameras, the Nikon D-series of digital SLR cameras, the Coolpix series of compact digital cameras, and the Nikonos series of underwater film cameras. Nikon's main competitors in camera and lens manufacturing include Canon, Sony, Pentax, and Olympus.</p> <p> </p><div><img> <div> <div><img> West Building of Nikon in Nishi-Ōi,Tokyo</div> </div> </div> <p>Founded in 25 July 1917 as <i>Nippon Kōgaku Kōgyō Kabushikigaisha</i> , the company was renamed Nikon Corporation, after its cameras, in 1988. Nikon is one of the companies of the Mitsubishi Group.</p></p>				es