SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3f7c1548d1b14c512e5f25dd6533122ef4681df05626e81334bf96290223055d' 
  AND token = 'wJ9MEOwMARFLHm9i/jUkrXj9nXejLgakKYgDVciPrsM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}