CONCAT_WS in custom sql query

Question

I'm trying to run a custom sql query against the WordPress wp_postsmeta table. However, I can't seem to get CONCAT_WS to work as it did when I ran the query in the MySQL command line.

Right now I'm just trying to get CONCAT_WS to work. This is the relevant code:

global $wpdb;
$query = "SELECT $wpdb->postmeta.post_id, CONCAT_WS(',', $wpdb->postmeta.meta_key, $wpdb->postmeta.meta_value) from $wpdb->postmeta;";
$result = $wpdb->get_results($query, OBJECT);

This is $query from the end of var_dump: [...] 'SELECT wp_postmeta.post_id, CONCAT_WS(',', wp_postmeta.meta_key, wp_postmeta.meta_value) from wp_postmeta' (length=105)

This is what is returned:

0 => 
  object(stdClass)[2912]
    public 'post_id' => string '2' (length=1)
    public 'CONCAT_WS(',', wp_postmeta.meta_key, wp_postmeta.meta_value)' => string '_wp_page_template,default' (length=25)

Seems like it returns part of the query in the result.

Is CONCAT_WS not possible to use with WordPress?

Answer 1

'CONCAT_WS(',', wp_postmeta.meta_key, wp_postmeta.meta_value)' was the name of the column. Everything is working as it should.

To change the name of the column, add AS name after the CONCAT_WS statement, like this:

'CONCAT_WS(',', wp_postmeta.meta_key, wp_postmeta.meta_value)' AS name (I didn't test this specifically).

Now the new column will be called name.