SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de0bb46ca730a6d4ba2c2f8191d751f0f63ff26afdcafab6d8fe1de8ea20d5be' 
  AND token = 'VpmrZCUjA0gYwwjvSJ2HOKcKJaToH6Jz4zwORIUTJew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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