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The really hard way is to create a custom SQL query.

The easier way would be to get all the terms for year and then in a loop do multiple wp queries.

Or you could just query all the data you need, including the year terms into an array and do a php usort()

Thanks.

Although really hard, your first suggestion is more appealing to me.

I assume that if I construct the correct query, I will be able to use native WP functions to display the results. Am I correct?

Yes and no.

There are different way of building a custom SQL query.

1. The simpler – just a Query – which will return an array ( or object ) which then you apply php functions to, but as it wont modify $posts then ‘standard’ wp functions wont work

2. or harder, modifying the WP_Query method SQL with filters which then will return a $posts object which you then can use wp functions like the_title()

3. or a different approach is the write a custom query and then build a $posts object

It all depends on the research / rabbit hole you want to go down.

If you want to do it totally the WP way then option 2 using filters such as ‘posts_where’ and ‘posts_orderby’