SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78932c956abfc13e39c9b17ff0abceb7dd286f4d2cb8bca4b83843e74c02e9d9' 
  AND token = 'i3Wm92lopTDIl+/GYBSZ6LrN2aUz5wBRYGZe9OqziGc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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