Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '56ee215f7429bd7b0f7cb3d56a7c4aab69820dfcb62119b17958bfc1ddb93758' 
  AND token = '6oKDUmJf0Pb0tAyeNVMiUiRZgWeN+E5QBWsKi+ZD4ZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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