SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '329c78f3393504351f02163b80560079f35d5c80c2a2aca1b85af53149e166aa' 
  AND token = 'L9PZWfmaGhCwH/6yilElQtstIWW7cwTdq4Y7+ZcVGGw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}