SELECT 
  1 
FROM 
  cscart_june_setupec_print_temp_designs 
WHERE 
  session_id = 'PLCK-C5BI-WE5Q-PD4Q-S7JV-BJ80-52QC-OZ14' 
  AND product_id = 74 
  AND expires_at > 1781888620 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00037

JSON explain

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