How to merge these two post queries?

The answer is “take the array from the tax_query argument in the first query, insert it into the second and change the relation to OR”.

In other words, to use a single query with the following in the arguments …

(As stated before, $terms_list_ids was already generated; it contains the IDs of Company terms which have meta that matches the current Topic term).

Credit for the answer goes to a Reddit user.

  // taxonomies
  'tax_query' => array(
    'relation' => 'OR',
    // Posts related to a Company with this Topic...
    array(
      'taxonomy' => 'company',
      'field'    => 'id',
      'terms'    => $terms_list_ids,
      'include_children' => true, // <<< IMPORTANT
    ),
    // Or...
    // Posts with this Topic directly...
    array(
      'taxonomy' => 'topic',
      'field'    => 'slug',
      'terms'    => $topic_term->slug,
      'include_children' => false,
    ),
 ),

Related Posts:

  1. Can wp_query return posts meta in a single request?
  2. Broken? WP_Query and “attachment” as a post type
  3. Order by DESC, ASC in custom WP_Query
  4. Exclude or Include category ids in WP_Query
  5. Secondary Sort (fallback) for WP_Query
  6. Changing the meta_query of the main query based on custom query_vars and using pre_get_posts
  7. Query Posts in a Predefined Order
  8. How to paginate attachments in a secondary query as gallery?
  9. How to stop wordpress to make the default query?
  10. How to make an activities stream mixing posts and comments?
  11. WP_Query based on URL parameters
  12. Order by meta_value_num DESC and meta_value ASC on WP 4.0
  13. Order posts ascending with number in title
  14. How can I style future post?
  15. List taxonomy terms plus their latest post ordered by post date
  16. WordPress altering my custom query, How to fix it?
  17. using wp_query to return posts w/ comment count > 0
  18. Order by meta_key in custom post type doesn’t affect the query
  19. Is there a PHP function that can match anything after the given URL, so my IF statement will work in each instance?
  20. Add a default meta_value to new posts
  21. WP query exclude post within the last month / only show over 1 month old
  22. WordPress query for most recent posts from multiple categories
  23. Too many posts cause slow load when paginating
  24. Order Posts by meta value AND published date
  25. Pass array of taxonomy terms to wp_query
  26. Comparing dates in custom field
  27. List of the years with posts presented
  28. Query custom post type by custom taxonomy (category slug)
  29. Advanced Taxonomy Queries WordPress
  30. Use post object from first query in second query
  31. Getting post revision and printing them on the post content site
  32. Editing the default wordpress search
  33. Slow page loads due to WordPress Core Query
  34. wp_query for multiple cities (multiple values in a metabox)
  35. Adding column to wp_posts table or join wp_posts table with another table
  36. get posts by meta_key from inside key of post meta
  37. Help optimizing slow WP_Query with meta_query
  38. meta_value_num not ordering all items
  39. Pre-Populate $wp_query settings with custom rewrite rules and custom template_redirect
  40. exclude a post from wp_query loop
  41. Is_single() conditional tag returns null in query
  42. Pass $page_id to new WP_Query
  43. Is it possible to query a custom field where the value is between two fields?
  44. WP_Query args to show posts from specific custom taxonomy
  45. How to query woocommerce product by pricing? [closed]
  46. Can I modify a WP_Query instance or clone it with modifications?
  47. Include posts from some categories while excluding from others
  48. filter wp_query result with custom field values
  49. Posts in loop all show the same author when there are many authors
  50. Show a 404 error page if Public query variable’s value doesn’t exist?
  51. WP_Query within function within WP_Query
  52. If have posts a week old, display, else display a different loop
  53. All blog data on a page using custom query gives 404 for page 2 and onward
  54. Daily drip of posts – based on user ‘startData’ – ordered oldest to newest
  55. How to add tax_query to $args with concatenation
  56. Where is the extra SQL fields coming from?
  57. construct complex queries with WP User Query
  58. How do I fit WP_Query arguments into a function?
  59. Create one-use post dynamically, add to main query, do not insert post (user profile view)
  60. How to create a widget like this?
  61. Does query_posts have an effect on get_the_category?
  62. Second loop pagination changes URL, not content
  63. Why always one post missing
  64. Help with Wp Query
  65. Is there ANYTHING about this query that’s incompatible with WordPress 2.9.2?
  66. tax_query in pre_get_posts
  67. get all images from the wordpress media library with link to the post they are associated with
  68. adding pagination to a foreach loop in wordpress
  69. Add metabox if there is at least one post available
  70. WP Query – grouping posts by same meta key, adding together values from another key
  71. setting offset to category number in archive page
  72. Retrieve all custom field values of a specific custom field metakey as an array, inside WP_Query
  73. Pass post ID to JavaScript outside the loop
  74. Query for current post
  75. Access queried post ID in WP_Query
  76. Loop through array of pages
  77. wp_insert_post with ACF Fields and WP Meta Query returns no rows until update
  78. Query WP Posts, then list the taxonomies from those posts
  79. Query post with content only
  80. Load WP Query with Ajax
  81. Search with WP_Query, but ignore href URLs in anchor tags?
  82. Displaying Pages in Nav Sub-Menu with Specific Taxonomy Terms?
  83. Is meta_key used for ordering, filtering, or both?
  84. compare for multiple meta values for same key in wp_query
  85. Taxonomy Terms That Don’t Exist Display Results
  86. Why is my query not giving results?
  87. Fetch only categorized posts
  88. Wrap group of wp query posts to parent div by date/year
  89. Wrote a WP Cron Plugin and it triggers a fatal error upon activation
  90. Add pagination to table generated by wp_query
  91. Adding a Theme Customizer Control for Posts_Per_Page
  92. using next-page and previous page inside a wp_query
  93. Custom query from all posts & all child page from one parent page?
  94. Get the type of an advanced custom field (ACF) in a WP_Query loop [closed]
  95. wp_query conditionally get posts
  96. Getting Year & Date inside wpdb [duplicate]
  97. restrict posts per page
  98. the_excerpt() not working in custom archive
  99. Get posts by meta value except one post [closed]
  100. How to efficiently find “duplicate” posts, where the titles are different, using metadata to match posts?