Sorting dependency

[olafgleba]

Hi,

maybe i am too simple minded today, but my guess is that the following task is not possible(?):

I have two datetime fields in a template, lets say Date_1 and Date_2. The template output ($pages->find()) is sorted by Date_1 in descending order. Now, if Date_2 is populated it should join the result output chronological.

Example:

I have 3 Pages

1. Page => Date_1: 08.2.2023, Date_2: Ø
2. Page => Date_1: 06.2.2023, Date_2: Ø
3. Page => Date_1: 05.2.2023, Date_2: 07.2.2023

The default sorting gives me this:

• 1. Page
• 2. Page
• 3. Page

Desired result:

• 1. Page
• 3. Page
• 2. Page

Please, i would be delighted if you proof me wrong. ?

Many thanks in advance
Olaf

 

[Jan Romero]

The way ProcessWire selectors work, this should be sort=-Date_2|Date_1, although I’m neither sure where the hyphens go nor whether sorting allows the pipe operator at all.

Alternativey, it’s easy in SQL with coalesce(), or you could add a hidden third field that precomputes to Date_2 ?? Date_1.

Edit: doesn’t seem to be supported judging by this open PR https://github.com/processwire/processwire-requests/issues/107

[olafgleba]

As both fields may be populated and wanting the behavior nonetheless, the "if one is empty, than..." doesn't fit anyway. But you gave a good hint with that hidden field approach. Thats the way to go, i think.

Many thanks!

[monollonom]

I have the same case where I use a start date and an end one. I add a hook that checks the end date when saving the page and if undefined it copies the start date value, this way you can sort using the end date.

[monollonom]

?

Edited March 22, 2023 by monollonom