Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37ad6a1db6c23ad76b6c476ff6df7d8c669e8fd3692f3781d96edc2f2e2a6841' 
  AND token = 'c2mdR0X5dVMoeMSqww0WkenGlBwATb9vObxjuUXvubQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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