SELECT 
  1 
FROM 
  cscart_aprilec_print_temp_designs 
WHERE 
  session_id = 'PMKL-ME3O-LKV4-MBAU-2S1W-ETH9-D5XX-TC9E' 
  AND product_id = 208 
  AND expires_at > 1777123100 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00090

JSON explain

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