Sandbox

SELECT 
  redirect_id, 
  src, 
  type, 
  object_id, 
  dest, 
  lang_code 
FROM 
  cscart_seo_redirects 
WHERE 
  src = '/electronics/cameras-and-photo/camcorders/f50-flash-memory-52x-zoom-camcorder-silver'

Query time 0.00033

JSON explain

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