SELECT 
  1 
FROM 
  cscart_aprilec_print_temp_designs 
WHERE 
  session_id = '1MZA-002S-DO6S-7Z8E-ORNF-PE84-3G8A-54EO' 
  AND product_id = 74 
  AND expires_at > 1778209400 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00040

JSON explain

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