SELECT 
  1 
FROM 
  cscart_aprilec_print_temp_designs 
WHERE 
  session_id = '4Z3U-S3A7-DU4J-8TR0-459J-QZD1-XJRE-NKGV' 
  AND product_id = 203 
  AND expires_at > 1777640766 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00047

JSON explain

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