Which is faster wpdb & get_row or wp_query & ge_post_meta?

Im planning to make a private api and i was wondering which one should i use go for my datas.

1. wpdb & get_row with my custom sql
2. regular wp_query & get_post_meta()

Im wondering if it’s better to create a custom table & used wpdb/get_row or just use create a custom post type & post meta instead.

Im newbie at this so i wanna know which one from the two would be faster??