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In WordPress WP_Query, tax_query is a powerful tool for querying about taxonomies. This tool allows you to build more detailed queries that combine multiple taxonomies or use relationships such as AND and OR.
Here is an example of a complex query using tax_query
'tax_query' => array(
'relation' => 'AND',
array(
'taxonomy'=>'category',
'terms'=> array('pickup'),
'field'=>'slug',
' operator'=>'IN'
),
array(
'relation' => 'OR',
array(
'taxonomy'=>'tax_island',
'terms'=> $tax_island,
'field'=>'slug',
' operator'=>'IN'
),
array(
'taxonomy' => 'tax_pickup',
'terms' => $tax_pickup,
'field' => 'slug',
'operator' => 'IN',
)
,
),
)
This example queries the category taxonomy with the slug pickup and either the tax_island or tax_pickup taxonomy with the specified slug.
The default for relation in tax_query is AND, but by combining relations by nesting them as shown above, it is possible to query for various combinations of conditions.
As you can see, tax_query makes it easy to create taxonomy queries with complex conditions, so please make use of it according to your requirements.
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