Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '750043537725ec4d907e9f87fb379d349c062abf030234b9e440d9534397d121' 
  AND token = '4/zb8nOCPAt90hGMhj2+gceiNwsAc5pWVUXmVmwweDg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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