data-order (html5-attribute) attribute is not working. about jquery-datatables-rails

[smisch]

One possible explanation for data-order not working as expected is that the first row has an empty value:

<table>
<thead><tr><th>Column</th></tr></thead>
<tbody>
<!-- will not sort correctly due to empty data-sort attribute -->
<tr><td data-order="">NULL</td></tr>
<tr><td data-order="975020400">24.11.2000</td></tr>
<tr><td data-order="1416783600">24.11.2014</td></tr>
</tbody>
</table>

In this example the column will not sort correctly. It's important that the first row has the empty value. If only the second row has an empty value, sorting will work just fine:

<table>
<thead><tr><th>Column</th></tr></thead>
<tbody>
<!-- will sort correctly regardless of empty data-sort attribute -->
<tr><td data-order="975020400">24.11.2000</td></tr>
<tr><td data-order="">NULL</td></tr>
<tr><td data-order="1416783600">24.11.2014</td></tr>
</tbody>
</table>

My guess is that the empty data-order attribute is confused as a string and enables the alphabetical sort order. Maybe the type detection could be fixed so that it doesn't confuse empty data-order attributes with strings and enables the numeric sorting feature even if the first n rows are empty.

Otherwise a simple fix is just to convert numerical values to integer so that empty values will be represented as 0:

// PHP
<td data-order="<?php (int) $timestamp; ?>">

<!-- Smarty -->
<td data-order="{0 + $timestamp}">

[ricardodovalle]

@mitsuthar
Could you try again against last updates, please?
The gem is using last stable dataTables.js (1.10.0)

[ricardodovalle]

@mitsuthar
Closed by user inactivity.
Please reopen if the error persist or to post the answer.
Thanks.

[antoniovassell]

Having the same issue here. @smisch has a solution for dates but am thinking what about numbers where I don't want to assume "0" when there is a missing value since "0" not necessarily means NULL in some situations.

[althaus]

Stumbled upon the same issue today.

[Jlesse]

Also stumbled on this issue. Any news?