SELECT 
  1 
FROM 
  cscart_aprilec_print_temp_designs 
WHERE 
  session_id = 'F9XV-WH7C-P2KA-C4W6-LM5O-A9VM-WZ7H-4OT8' 
  AND product_id = 218 
  AND expires_at > 1777333152 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00043

JSON explain

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