SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '908e7e3368d7b3f7a5410a023133feabcd2fc61f26183842d47040c7472520d7' 
  AND token = '8HcVo25FS1Nj5Y1MEAdYGPifS72RIiQwqEfDkwOkJu0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}