SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '213190d162684674f27e1db983614c52427b77a69c11e95a2611093caf15ede9' 
  AND token = 'IRNbIxwd6Gsbc94qnSipXnFuWFoGCycvJT8+WnbPI/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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