SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '0cc17157e9a8f6937e9f6729fac51c15803f93fbfe326e52884cc034422e031b' 
  AND token = '2wQwBZTqRNb1jQu55Beb8bpRJ/E+vu4BtjIW+L4WhgM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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