Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c91a6a12256eac4834aec408c33228941b43d7165c3049c1ea61c5794dc3398b' 
  AND token = '7p1nIyZ0RzWnOxQhUcdkP0xHXidsvwQAFFjiBDLmtq0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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