WP_Query with MetaQuery issue

Question

I'm facing a rather strange issue when attempting to pass in four different meta_query values to my WP_Query.

Find below an example of my WP_Query search. Please bear in mind, if I remove and test each of these meta_query on there own, they work fine. It's just when they are being passed in as four do I not get any results. Even if I leave the values blank I still receive no posts in my query!

$v_args = array(
    'post_type'     =>  'loads_available',
    's'             =>  "Post Name", 
    'meta_query'    =>  array(
      array(
            'key'     => 'type_of_load',
            'value'   => "Frozen",
            'compare' => '=',
          ),
        array(
            'key'     => 'number_of_pallets',
            'value'   => 2,
            'compare' => '>=',
            'type' => 'NUMERIC'

          ),
        array(
            'key'     => 'type_of_trailer_required',
            'value'   => "Trailor",
            'compare' => '=',
          ),
          // ^ problem
        array(
            'key' => 'euro_pallets',
            'value' => "Yes",
            'compare' => '='

            )
        )
    );

    $loadsAvailableQuery = new WP_Query( $v_args );

Now I would just like to make it clear, these meta_query values work fine on a individual basis, it's just when I start trying to use them in conjunction with each other for example.

Search query would be:

Post Name: "Post Name" Type of Load: "Frozen" Number of Pallets: 5 Type of Trailor Required: "Trailor" Euro Pallets: "Yes"

This would not give me any results, even though I am sure there is posts meeting the criteria. It's feels like I could be missing something in the Query, I read about use relation but that defaults to "OR" - which I believe would be the correct value here.

Are there any common misconceptions or obvious flaws in my code that I'm not quite seeing here?

Many thanks for the responses.

Answer 1

You may want to try adding the 'RELATION' => parameter into your meta query array so that you can encompass all of your meta values. Something like this:

    $v_args = array(
    'post_type'     =>  'loads_available',
    's'             =>  "Post Name", 
    'meta_query'    =>  array(
      'relation' => 'AND',
      array(
            'key'     => 'type_of_load',
            'value'   => "Frozen",
            'compare' => '=',
          ),
        array(
            'key'     => 'number_of_pallets',
            'value'   => 2,
            'compare' => '>=',
            'type' => 'NUMERIC'

          ),
        array(
            'key'     => 'type_of_trailer_required',
            'value'   => "Trailor",
            'compare' => '=',
          ),
          // ^ problem
        array(
            'key' => 'euro_pallets',
            'value' => "Yes",
            'compare' => '='

            )
        )
    );

    $loadsAvailableQuery = new WP_Query( $v_args );

Depending on your use case, you may need to set up a variable based on the user query to toggle the relation parameter in your query.

Note the relation parameter can also be set to 'OR'.

Checkout the meta_query section inside of the WP_Query codex