SELECT 
  1 
FROM 
  cscart_aprilec_print_temp_designs 
WHERE 
  session_id = '3I6E-P0GI-JXHC-1R7B-NEWF-OUOA-IGK0-HC3S' 
  AND product_id = 56 
  AND expires_at > 1777404195 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00036

JSON explain

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