SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84abd32ee88ff9972042770025bcd704e3cc878bdfb4fc8164dc0b95fa6247ff' 
  AND token = '3WG7VU37zyjaA9uQE7fwHuXwiOGgIGjTqtfhKpqfyLQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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