SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45eea604bece32c3b4ab183335e5867efdc238f5d7bbf96553f726dfc76eddf0' 
  AND token = 'cu6KiMXy8hPFtVXvVGQgEcjZux1wVY+FV3lJJSAL/XI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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