Some ideias to create Views Tables from WordPress data in case you need to make custom queries in the database.

wp-view-tables.php

<?php
	
function _create_views() {
	
	global $wpdb;
	
	/*
	* Post Type book and its ACF custom fields
	*/
	
	$sql = "
		CREATE OR REPLACE VIEW view_books AS 
		SELECT 
			p.ID AS ID,
			p.post_title as post_title,
			p.post_content as post_content,
			pm1.meta_value AS author,
			pm2.meta_value AS isbn,
			pm3.meta_value AS pictures
		FROM wp_posts p 
		INNER JOIN wp_postmeta pm1 ON ( pm1.post_id = p.ID AND pm1.meta_key = 'author' )
		INNER JOIN wp_postmeta pm2 ON ( pm2.post_id = p.ID AND pm2.meta_key = 'isbn' )
		INNER JOIN wp_postmeta pm3 ON ( pm3.post_id = p.ID AND pm3.meta_key = 'pictures' )
		WHERE p.post_type = 'book'
		";
		
	$wpdb->query($sql);
	
	/*
	* Books attributes "Repeater Field"
	*
	* The trick is to use the first sub field to return the length of the repeater, 
	* then use inner join to get the other sub fields to map as columns.
	*/
	
	$sql = "
		CREATE OR REPLACE VIEW view_books_attributes AS 
		SELECT 
			pm1.post_id AS post_id,
			pm1.meta_value AS name,
			pm2.meta_value AS value
		FROM wp_postmeta pm1 
		INNER JOIN wp_postmeta pm2 ON ( pm2.post_id = pm1.post_id AND pm2.meta_key = REPLACE( pm1.meta_key, '_name', '_value' ) )
		WHERE pm1.meta_key LIKE 'book_attributes_%_name'
		";
		
	$wpdb->query($sql);

}